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H4D- 40 back on an Alpa

Hey Guys,
Alpa has Been on my mind for a while (after reading these forums) :rolleyes: I was just wondering if anyone has actually tried the 40 back on a tech camera and would it be totally useless? I can't really afford to buy another back and an Alpa.

Cheers
Will.
 

Professional

Active member
Search on "Fun with MF" and you will see there is someone using his H4D-60 back on Alpa TC, in fact i am also looking to get Alpa camera and attaching my H60 on it, i know i need few accessories as connections and battery, but as long it can be done then alright.
 
Thanks Tareq, The 60 is ok with the Alpa, its more the fact the 40 has micro lenses and from what Ive heard its not recommended to be used on a tech camera but Im wondering if anyone has done it or can give some advice on this setup.


cheers
Will.
 

jlm

Workshop Member
the problems with the microlenses have to do with angle of incidence at the sensor and are only a problem at the far edges/corners when the back is shifted. no shifting, no problem
 

stephengilbert

Active member
ALPA's admittedly conservative answer regarding the P30+ microlensed back:

Can I use my Phase One P30(+) Back with the ALPA?

The target group for this back type are fashion photographers. It uses a special sensor and is also optimised for high ISO. The backs fit mechanically, of course. But according to user tests the microlenses used with this sensor produce a severe color cast when using moderate to extreme wide angle lenses and/or movements (shifts, rise, fall, swing, tilt). It seems that this can't even get cured with "Lens Cast Calibration". Therefore Phase One does not suggest the use of this type of back with technical cameras like the ALPA.


http://www.alpa.ch/en/glossary/phot...-use-my-phase-one-p30-back-with-the-alpa.html
 

johnnygoesdigital

New member
Hi Will,
If you don't have movement and don't go too wide, the 40 should be okay. Image circles should be good with the cropped sensor. I'm actually looking for a Alpa TC with a P30+
 

dougpeterson

Workshop Member
The P30+ is more than "not ideal" choice for a tech camera for wide-angle applications. It is a straight-up bad choice. It shows severe color cast with many lenses (e.g. 24XL, 35XL) even without movement, and extreme fall-off (to zero signal in many cases) with even modest movements. For macro/table-top applications where the lens is mounted pretty far from the back a P30+ can be an okay substitute for a back better suited for tech/view cameras. On a wide-angle it is a fool's errand - your selection of lenses will be severely restricted and your use of those lenses will be limited.

Perhaps I can make an exception for johnnygoesdigital assuming he wants to use the lenses with less steep light angles like the Rodenstock HR retrofocus lenses (e.g. 40HR) or longer lenses like the Schneider 72XL, since he will be using it on a body without the possibility of movement.

Still I think it's a much better option to invest in a back/body combo that can grow with you. If in the future johnnygoesdigital wants to add an Alpa STC or XY etc, or Cambo/Arca/etc with movement then he'll have to change backs.

The sensor of the H4D-40 has smaller pixels than then P30+. Conventional wisdom is that a smaller pixel with micro lenses will be more problematic (re: color-cast/fall-off with wide-angles and/or movement) than a larger pixel with micro lenses. I have NOT compared an H4D-40 and P30+ on a tech camera or used an H4D-40 on a tech camera. Normally we have a policy at CI of not even tangentially commenting on a brand we don't sell (e.g. Hasselblad) but physics is pretty brand-agnostic and I would strongly wager the H4D-40 would be even less forgiving for tech camera use than a 30+. That said, only the real world matters, not theory, so hopefully David can chime in if he has anyone that has braved the combo.

This is why the P40+ and all the Leaf backs have no micro lenses - the downside being that it loses that free stop of native ISO that micro lenses get you, which is a nice feature of the H4D-40.

I'd strongly consider if you can find a way to make an upgrade/cross-grade to an H4D-60 or any of the dozen+ Phase/Leaf/Sinar backs which are well-suited to use on a tech camera. The Phase/Leaf/Sinar would also have the benefit of having on-board power rather than needing to pack, carry, and connect an external power source. The H4D-60 also has a on-board battery system planned; you'd need to ask Hasselblad about a planned release time-frame for that.

Like I said, normally we wouldn't comment on anything related to a Hassy back, but this is the exact advice I'd give anyone asking about a P30+. Hope this doesn't offend anyone. We've had several P30+ customers who bought because they thought they'd never want a tech camera with wides or movements and then later had to change backs including Don Libby. It's always a bit painful when that happens (we, any good dealer would, try to help with the price to make switching easier but there is only so much you can do).

Doug Peterson (e-mail Me)
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jlm

Workshop Member
the H4D-40 works fine with as wide as 28mm; don't know if Phocus provides automatic colorcast correction
 

dougpeterson

Workshop Member
the H4D-40 works fine with as wide as 28mm; don't know if Phocus provides automatic colorcast correction
Jim are you referring to on a tech camera or on the H4D body?

The issue being discussed is limited specifically to tech cameras (e.g. Cambo, Arca, Alpa) where the lens is located very very close to the sensor. It does not relate to using standard SLR lenses on an SLR body.
 
I recieved this email, Not sure if the person was from here or My dealer contacted them because I emailed him for a quote, but this is what I recieved.

The ALPA 12 STC will work with your Hasselblad HD40. You will need to purchase the external battery holder and think which lenses you want to work with to match your sensor dimensions. The 23mm /24mm/28mm wide series of lenses will give you a good image circle and allow good movement over your sensor.


opinions? I appreciate all the comments so far, Maybe I could buy the Alpa and see how it goes and if its not upto par I may have to purchase another back or upgrade bodies....

Cheers
Will.
 

cmb_

Subscriber & Workshop Member
Will - the email does not address the issue of color cast and light falloff with micro lenses as outlined above by others. The email also suggests the Alpa 12 STC - a camera with movements and says that the 23mm, 24mm, and 28mm lenses will give you a good image circle and allow good movement over your sensor. I do not think this is the case - depending on how you define "good movement". The H4D40 is 33.1 x 44.2, correct? The 24mm has an image circle of 60mm - this will give you about 4mm rise or fall and about 3mm shift left or right. The Rodenstock 23 & 28 have 70mm image circles so you will get about 11mm rise and fall and 9mm shift left or right. The new Schneider 28 has a 90mm image circle so with that there will be room for movements.

It would be nice to hear from someone who has used the H4D40 with an Alpa and get some good information. As usual, some lenses will probably work much better than others.

Try to PM Nick-T who is a member here and always has very good info about Hasselblad.
 

goesbang

Member
Fellow travellers,
As some of you know, I am a firm believer that the Alpa system is the best all-round solution for landscape and architecture. I've made many posts here and elsewhere to this effect.
As I am a Phase One user and none of my friends who use Hasselblad have the external power supply necessary to test with my cameras, I could not express an informed opinion here.
Whilst there have been a few posts that have been helpful here, in particular from the ever-helpful Doug Peterson, the OP's question hasn't really been dealt with.
So, I did the next-best thing - I got in touch with some dear friends, Thomas and Ursula Capaul, who, apart from being fabulous hosts, also happen to be the owners of a small company in Zurich called ALPA. They've read this thread and know of a customer of theirs who has tried this HD/Alpa combo.
Below is a summary of what they had to say.

So far they had only one customer trying his back on a technical camera. Unless later soft-/firmware improves, their verdict so far: DISASTROUS! Even Rodenstock lenses without shifts produced...

a) a very strong color cast in general
b) a nasty shift to magenta (left and right!) that is persistent, especially in the shadows
c) strange noise artefacts in shadows
d) horizontal line artefacts

In fairness, this was based on only a single copy of this type of back but they ask us to be very careful in recommending such a combo. (I guess this is similar to Phase One's position on the P30+ on technical cameras)
If anyone has had better results, they would LOVE to hear about it, as I'm sure would all the Hasselblad users here. Alpa would, I'm sure, be only too happy to be able to sell their awesome cameras to Hasselblad users, but only if the results are worthwhile.
My friend Tareq has a HD60, so perhaps when we can find a way to power the back, we can run some tests with it on my ALPA STC. The comments above are, BTW, specific to the 40MP.
I hope this helps advance the discussion.
Note that the comments from ALPA would be relevant to ANY brand of technical camera as the problems outlined are the product of how the sensor behaves in response to light delivered through technical camera lenses, regardless of manufacturor. The camera itself is not a factor.
Cheers,
 
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goesbang

Member
Hey Guys,
Alpa has Been on my mind for a while (after reading these forums) :rolleyes: I was just wondering if anyone has actually tried the 40 back on a tech camera and would it be totally useless? I can't really afford to buy another back and an Alpa.

Cheers
Will.
I believe your back is currently worth a 40% discount as a trade in on a Phase ONe IQ series back :salute:
Might be time to talk to your local dealer......
 
the problems with the microlenses have to do with angle of incidence at the sensor and are only a problem at the far edges/corners when the back is shifted. no shifting, no problem
is it a problem with H4D 40 and HTS 1.5 for shifting ?
 

jlm

Workshop Member
my experience is that the H39 back works fine with my cambo wrs, using as wide as the Schneider 43 and shifting 10mm or more.

by the way, i power the back with the Bigwave power adapter, about $140, about the size of a cell phone. it has a powered fw port; you simply cable it into the back's fw800 port.

found this AE buddy reporting:
http://forums.gamesquad.com/showthread.php?54242-Big-wave-power-packs.

Woody has been showing quite a bit of work using his HD4-60 with the shiftless alpa TC and no problems.

regarding the HTS, that adapter adds another lens and increases the focal length by 1.5, probably helps with vignetting and gets space to tilt
 

Woody Campbell

Workshop Member
I'm shooting an H4C - 60 back on an Alpa TC and an Alpa Max. I have the 36mm and 48mm Schneider APOs - I'll probably add the 120 at some point. I power it with an Imagebank II (which I had laying around anyway) and a really big Sony battery so i don't have to worry about battery capacity. Hasselblad has gotten fuzzy on the delivery date on the external battery holder for the 60.

The Phocus scene correction feature does an excellent job of correcting for color shifts (on the TC) and if you wish vignetting. Note that the corrections for color shift are relatively small which is a good thing because the corrections are using up dynamic range (in different amounts in different channels which if significant will result in color clipping) and if extreme would have a bad effect on IQ. I suspect that this would be a serious problem with a micro lensed back - we're using these somewhat ad hoc combinations of gear in search of 4x8/8x10 IQ and an extreme color shift correction goes in the wrong direction (even if it produces more or less correct colors).

On the Alpa Max the situation is more complex - I'm exploring this as I write this. I just got the 48mm last week - I've had the 36 for some time, but its 90mm image circle is relatively tight to my back's 70mm diagonal when you account for quality drop off as you approach the edge of the circle. The new 48 has plenty of image circle.

Here's the issue with the H4C-60: for shifts along the long axis of the back (right and left shifts with the back in landscape orientation) there is no issue. For shifts along the short axis of the back (right and left shifts the the back in portrait orientation) the images have a centerfold. I'm still exploring the exact limits (I haven't sorted out whether f-stop and focus make a difference, for example and haven't processed any images through a really critical cycle) - I had planned on starting a thread on the subject once I get these issues sorted. Scene correction in Phocus helps but does not eliminate the centerfolding.


As I said above I'll start a thread on this once I've had a chance to explore the issues fully (probably a couple of weeks from now).
 
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gazwas

Active member
As I said above I'll start a thread on this once I've had a chance to explore the issues fully (probably a couple of weeks from now).
That will be an interesting read Woody as I've never heard of this issue. Do all MFD backs suffer with this because of their large sensors and how does the fold appear in the image?
 

yaya

Active member
That will be an interesting read Woody as I've never heard of this issue. Do all MFD backs suffer with this because of their large sensors and how does the fold appear in the image?
Other backs such as your P+ have this corrected automatically in the software
 
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