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Which direction to go.. IQ250 v IQ260

Zerimar

Member
I have also seriously considered just keeping the P45+ and getting an a7r with the metabones adaptor to use canon lenses. It'd cost me around $17,000 less to go that route :chug:
 

Shashin

Well-known member
I would just go with what your intuition is telling you. Both backs are going to give great results.
 

ondebanks

Member
The IIQ file format also records only 14 bits, so even if the IQ260 has 16 bit A/D converters, the 2 last noisy bits are not recorded to the file, a wise engineering decision as it's just noise that would bloat the file. If one likes to look at those two extra bits of noise one should get a Hasselblad camera, as far as I know their format stores the full 16 bits coming out from the A/D converters.
Torger, I used dcraw to convert a raw file from a Hasselblad H3DII-39 to FITS format, and I found that the 16th bit was hardwired junk. The 15th bit appeared to contain real data, but of course that data only consists of oversampled noise variations, so it's pretty worthless.

I don't know if this is true of all the H-system DBs...I would like to test a few more raw files sometime.

Ray
 

Shashin

Well-known member
The results will, however, differ from a comparison made at 100% on screen.
If you think pixel pitch, i.e., 100% monitor view, is the criteria for DoF, then the IQ250 will still have less DoF simply because it has smaller pixels than the IQ260: 5.3um vs. 6.0um. An f-number equivalent of about 1/3 of a stop, which will be pretty insignificant.

BTW, in DoF, the print/display size and viewing distances are not fixed (unless you want to calculate DoF scales). They are simply variables and you can work with many combinations. It is easy to calculate or, to be more precise, model the appearance of DoF.
 

Shashin

Well-known member
Interesting news about the bit depth. As far as long exposures go, I'd sometimes push the p45+ as far as 10-15 minutes (I did a 3 hour one once for fun)

The idea of the iq180 is tempting given their used prices. I could sell my p45+ if I didn't keep it and have the 180. I've heard that back has tiling issues with skies though.

It appears I have 4 options:
1. Keep the P45+ (and most likely purchase a profoto 8a or two with my current 25% edu discount on profoto gear)
2. Keep/sell the P45+ and get an IQ180
3. Trade in the P45+ with around $20k for an IQ250
4. Trade in the P45+ with around $20k for an IQ260

I'm somewhat hesitant about the 250 because they most likely will inevitably release a full frame version of it. The debate on the frame size is interesting, especially with Will's above statement comparing both to my 1.1x crop sensor. I however do admit that I am not exactly keen on the idea of spending $20,000 to move to a smaller sensor than I currently have.
The IQ250 sensor is from Sony. It is being supplied to Phase, Hasselblad, and Pentax. It is uncertain how Sony is going to supply the MFD market. I don't know how much I would bet on a FF 6x.4.5 sensor from Sony.

Also, from things I have read here, an IQ160 would be better than an IQ180 in terms of lens cast. The 180 series backs seem very sensitive to that. Not that lens cast can't be fixed, but it is a bit of a pain.

The lighting idea might not be bad. It really depends on what you want to do when you get out (and maybe when). The p45+ is no slouch in the studio. If you are looking to pursue studio photography, maybe that is the better route--the cameras can always be rented (lighting too, but an empty studio does not impress the visitors).

Either that or, with the money you will save, buy an iPhone and go in live in southeast Asia for the rest of your life. Not a bad option if you thing about it.
 

Paul2660

Well-known member
The idea of the iq180 is tempting given their used prices. I could sell my p45+ if I didn't keep it and have the 180. I've heard that back has tiling issues with skies though.
Rick,

If you are using a 180 on a Hasselblad, or other SLR style camera with a mirror box, the issues with color cast should not be a problem. Color cast is more an issue with the Tech Camera lenses, due to the fact the lens is much closer to the sensor, i.e. no mirror box. This is also a problem with wides not normal or telephoto lenses.

Tiling, this can be a problem with any of the P65, or IQ backs, full frame, but it should be totally controlled by software/firmware on the back. Each back will have a calibration file, which helps to control this issue and sometimes, the backs, need to be re-calibrated. Sometimes this can be done by a dealer, other times the back needs to go to Phase One. The file also may have to re-calibrated after a year/ or two as the back ages.

Tiling can also be more problematic with a tech camera, again due to the close proximity of the lens to the sensor. The Schneider lenses, (from my experience with the 160, 180 and 260, seem to have a bit more problem than the Rodenstocks. Here the LCC is a very important tool to help get the file to look right without tiling, especially on large shifts.

If you look at the face of the 180 or 260 chips, (all full frame chips actually), you will see faint lines that seemingly break the chip into 8 segments. These are readouts that allow the data to be fed off the chip and if the readout is not calibrated just right, one of the segments may show up just a bit darker than the one next to it, thus creating the "tiling" line.

I have not seen the face of the Sony chip, in the 250, so I am not sure if it's like the full frame chips, with the read out lines, or like the older Kodak chip in the P45+, which does not have these, at least I never noticed them on mine (wish I still had that back).

Paul
 

Zerimar

Member
Thank you for the further explanation of that Paul. I don't see myself using a view camera anytime soon (though using the canon 17mm ts-e with a phase back is an interest to me)

Is there any particular reason you wish you still had the p45+? It's a great back and has served me well through the years.
 

Paul2660

Well-known member
Rick:

I would have kept the P45+ if I could have afforded it. I have yet to see anything from the IQ260 at 45 minutes to 1 hour from any photographer, so I don't really know just what it will do. In my current environment in Arkansas, I would be best limited to 15 minutes, due to outdoor temps and humidity.

My main reason for the upgrade (at the time to a 160) was the larger MP count which I can justify in my printing as I specialize in large prints. I have yet to find any magic solution that will take a 20MP image up to the same quality as a 60MP or 80MP back's output. I realize you can stitch, but to be honest there are many times I either just don't want to stitch or the conditions won't allow it, and most of my outdoor setups are not ideally perfect level, as a nodal stitch required for optimum results.

I also was moving to a tech solution for wides and realized immediately the need for a better LCD on the camera as the one on the P45+ is not good for image review. Sure it can be done, but way too much time involved and even then the image at 100% is not very helpful. The IQ interface and LCD are excellent, and make for a much easier working environment.

At that time late 2011, I was offered a very reasonable trade-in amount for my P45+, but trust me yours is much better as it's 2014 and it appears you are still being offered 20K for your P45+. (Ed discounts don't really mean much as they are just a means to an end. Phase can or could work out the same process for other photographers if they wanted to).

My P45+ was pretty much at best a iso 200 camera as at iso 400 the overall quality of the image was just not worth it due to noise, loss of color, and saturation (this with non tech camera) I can't count the times I have needed good clean iso 400 and just can't get there with MFD unless I drop into Sensor plus.

By moving to the IQ260, I unfortunately drank to much Kool Aid (a term from my distant past in marketing), hoping to see that Phase One could bring a useable iso400 to the 260 at full resolution. The 260 has better results at 400 than my P45+, but still they won't hold up at full resolution, noise and fine detail loss is very apparent. The results at 400 in Sensor plus are much better and but here you have dropped 3/4's of your resolution. Too much of a trade off for my work. That's why I had suggested a used 180, as here you get 20MP Sensor plus and it does make a difference in printed work.

Looking back on my career, to be in college still with all the amazing advances that have happened in just the last 5 years, I do envy you. Personally, I would wait till at least Photokina, and see what gets announced. If you depreciate this type of purchase (always amazes me how many people don't seem to understand the idea of a book loss) the 250 is still the best investment long term. No doubt the P45+ you have will still have the same or maybe more trade in value (I was offered 24K in 2011 for mine which was 3 years old almost 4 and well used).

I also don't think when Phase One announces a full frame CMOS, (unless the chip is from Sony) that the value of the 250 will drop much. Sony has an excellent track record on chips just look at the DR of the D800 Nikon and this new chip is showing even better results. If the full frame CMOS is from Dalsa, or some other company it won't have the same background stable as Sony has, so it will take some time to see just how well the chip does.

Paul
 

kdphotography

Well-known member
I'd look at any of the IQ series offerings as well as consider the Leaf Credo. The interface alone is vastly superior to the P+ series and makes using the MFDB so much easier and more enjoyable. All produce stunning image quality, and I doubt there would be any meaningful difference in real world use, unless you photograph brick walls for a living. :D

When I moved from the P45+ to the P65+, I was initially hesitant about losing the long exposure capability of the P45+. Quite frankly, I don't miss it much at all, as I've found that 99.9% of all my photography is handled just fine with the 1-2 minute limits of the IQ180 and her sisters. I'm currently with an IQ180 using a DF body and Cambo WRS. I've played with the IQ250/260 and felt absolutely no enabling urges. ;) The IQ250 was definitely a neat match with the Alpa FPS and Canon t/s lenses.

If Live View is an absolute necessity, then the IQ250 wins hands down. Of course, all the IQ series and Credos can also take advantage of the Surface Pro tethering option with USB3, which makes for a nice enlarged extension of the MFDBs screen-- and much better than the WiFi options offered by the IQ2 series.

I agree with Paul here. Visit a dealer and try the various IQ MFDB and Leaf Credo Options to familiarize yourself and see how they suit your photography needs----and then wait for Photokina to see if something else is offered that might sweeten the pot.

:) ken
 

f8orbust

Active member
I have also seriously considered just keeping the P45+ and getting an a7r with the metabones adaptor to use canon lenses. It'd cost me around $17,000 less to go that route :chug:
You know, that makes a lot of sense (not just financial).

Have you seen Chris Barrett's comparison of the A7r and IQ260 ? As a quick, down-and-dirty, non-scientific test: Download the tiffs, go to PS, stack and auto-align the retouched images (don't down-res the IQ260 image, up-res the A7r), then switch the top layer on and off so you can compare the two. Hard to believe one came from a $35k capture device, and one from a $2k one. CB says he prefers the IQ260 image; I don't know - it's a tough call, there are things to like in both, and IMO it's pretty much a draw. In a blind test I suspect most people would have a hard time picking between the two. Guess it just goes to show what a leveler great glass can be (he used a S/K 35mm for both images).
 

Paul2660

Well-known member
IF the test from Chris was the indoor test, then it's the same stuff he posted in LuLa, and in that test, the A7r, D800 etc any Sony CMOS is going to win. The 260 is not, a low light camera, unless you can expose for several seconds maybe 30 seconds or so, but even then, the CMOS chip may still win out.

You can also look on LuLa for the tests, extensive, that DT did indoors, where they compared the 250, 260 and 280, again, the 250 won this test pretty much hands down expect for the output resolution part. You can expect the Sony A7r/D800 albeit slightly different sensors to have the exact same performance as base iso. Here is a link to some of the Lula posts:

Comparisons From DT's 250 and 260 testing in the Library

The 260 will do great at base iso (not sure if it's 100 or 50 now), but you still have to really watch for the shadows as they just can't be pushed too much.

CCD = more light the better.

Paul
 

Zerimar

Member
At this point I am thinking that the 250 may be the way to go for my work. I like that it's a faster back, has better battery life, can be usable at and above ISO 400, and it seems to be the much better performer for the long exposures I am so used to getting with my P45+.

I do need a longer window than the 1 or even two minutes on the 180, and I know I'll never get a trade in offer like this again for my P45+. I'm also hoping to do some tech work/rentals with the kit, which should be in much higher demand than the aging p45+.

I think the 100 f2.2 with the 1.3x crop factor would suffice, and I could use the 50-110 more often handheld with some higher iso. I may pick up the 35mm so I have a wide angle lens (the 50 end of the zoom isn't wide enough as is with my P45+.

I'm also quite keen on the ideals that phase put into the back. I've had several times where I wished I was shooting somethig with my Hasselblad kit, but had to use the canon due to the ISO requirements or the fast zoom range (24-70 f2.8L II is quite an amazing lens for that system) I feel like it'd be hard for me to pick up another camera, where as the ccd 260 would start to fall under the same shortcomings as the P+ CCD.
 

Ken_R

New member
The IQ250 should be as good or better than the best DSLR sensors today meaning you can use it like you would one of those in any light condition and up to iso 3200~6400 easily and still get high quality results. It is an extremely versatile item.

For wide angle tech camera use I would choose the IQ260 no question but for use on an SLR the IQ250 is hard to beat.
 

ondebanks

Member
The 260 will do great at base iso (not sure if it's 100 or 50 now)
Paul, I hope this recent thread didn't make you have doubts about its base ISO. I don't think I've ever posted more often in a single thread than I did in that one - just working hard to straighten out the misconceptions.

The IQ260 base ISO is 50. On a MFD CCD system, base is always the lowest ISO available. The manufacturers aren't stupid enough to put in fake "pulled" lower ISOs (as it's identical to just setting +ve exposure compensation on your meter i.e. forcing overexposure).

Ray
 

Paul2660

Well-known member
Ray,

I was involved with that thread for a while, but it got over my head after a while. I have always assumed that the base on the 260 was 50, but that thread did make me wonder.

Paul
 

gazwas

Active member
The manufacturers aren't stupid enough to put in fake "pulled" lower ISOs (as it's identical to just setting +ve exposure compensation on your meter i.e. forcing overexposure).
I didn't keep up with that thread as I was traveling but I thought the OP was suggesting the exposure at ISO100 was identical to ISO50 on the IQ260 suggesting it is a fake setting pulled down by C1.

Are you saying you know the manufacturers (Phase One) are not stupid enough or just assuming? I've not seen captures to evaluate but if the results are identical at both settings (exposure, DR, noise) then why use the lower (fake??) ISO?
 

ondebanks

Member
I didn't keep up with that thread as I was traveling but I thought the OP was suggesting the exposure at ISO100 was identical to ISO50 on the IQ260 suggesting it is a fake setting pulled down by C1.

Are you saying you know the manufacturers (Phase One) are not stupid enough or just assuming? I've not seen captures to evaluate but if the results are identical at both settings (exposure, DR, noise) then why use the lower (fake??) ISO?
Without wanting to re-ignite the whole thing again here - it would be best if you would just read that whole thread through - but let me summarise it thus: there is only one ISO setting for a given MF CCD where applying the metered exposure conforms to the saturation-based ISO standard - the placement of the recorded RAW intensity of a grey-card with respect to the saturation level, the amount of headroom above that in units of stops, and so on. If you set a higher ISO and go with the new metered exposure for that ISO, you underexpose everything and signal to noise suffers. If you could set a lower ISO and go with the new metered exposure for that ISO, you'd overexpose everything (highlight stuff that shouldn't saturate, does).

I thought the OP was suggesting the exposure at ISO100 was identical to ISO50 on the IQ260 suggesting it is a fake setting pulled down by C1.
Not quite; towards the end of the thread it emerged that he was imposing the same exposure at the two ISOs. And then he attached significance to getting the same results from both! But obviously, same quantity of light, same sensor efficiency, same noise, same gain = same results, regardless of the ISO tag.

His mistake was to leap from those equal results to a conclusion that the higher ISO was base. This was ignoring the fact that for an ISO to be base, it must conform to the rule about intensity placement with respect to saturation when the exposure is metered at that ISO - whereas he was metering at ISO 50, and duplicating those shutter and aperture settings to ISO 100; this was setting up a conformal ISO 50 exposure, but sticking an ISO 100 label on it. He was not taking a real ISO 100 exposure, because that would capture a stop less light and underexpose, and you'd see right away that it wasn't base ISO.

In his defence though, there was something weird about the way that his IQ back's firmware was rendering the histograms at different ISOs, and that was skewing his impressions. It's important to assess RAW files directly through analysis software like dcraw, for a discussion like this.

Are you saying you know the manufacturers (Phase One) are not stupid enough or just assuming?
I'm being kind to them by assuming they're not stupid ;)

But really, they're not. Why would they want a load of angry photographers moaning to them about blown highlights?

Besides, there's also the optics of the situation - MFD backs generally come across as discordantly low-sensitivity already; they have that well-earned reputation for struggling at even a couple of stops above their already typically unimpressive lowest ISO. If the manufacturers added an even lower pulled ISO setting, it would only worsen that impression in the marketplace.

Ray
 

lance_schad

Workshop Member
notified today about the IQ150:
IQ series digital backs | Specifications

wonder if this will offer the same advantages of the 160 compared to the 180 with respect to wide angles
Jim,
The IQ150 is an IQ250 without the Wifi and the One Year Classic Warranty instead of the 5 Year Value Added Warranty.

It was introduced at Photokina as a lower priced solution priced at $29,990 vs $35,990 IQ250.

So it will perform the same way the IQ250 lens wise.

Lance
 

dougpeterson

Workshop Member
notified today about the IQ150:
IQ series digital backs | Specifications

wonder if this will offer the same advantages of the 160 compared to the 180 with respect to wide angles
The IQ150 is identical to the IQ250 except for it's lack of wifi and it's warranty (all IQ2 now come with a 5-year warranty including a loaner provision while IQ1 come with a standard 1-year warranty):
Meet the new IQ150 from Phase One - DT Blog

So, no, it has issues with movement using wide-angle lenses on tech cameras, especially wide symmetrical lenses like the Schneider 28XL and 35XL.
 
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