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Blurred images on the 39mp back

Chris Giles

New member
I'm at 39mp now and I did the usual comparison to my 22mp back. I was a little surprised how soft the 39 looked in comparison but have nailed it down to the shutter not being fast enough.

With 35mm you'd match the shutter speed (or greater) to eliminate handshake. With the smaller pixels of the 39 back showing them more, is there a formula for I can apply to MF?
 

Shashin

Well-known member
But if you print both the 22MP and 39MP at the same size, the images are as sharp as each other.

You need to find your own limit. With digital it is simple because you have an instant result. Test focal lengths with shutter speeds and you can find out what you need for the results you want. I can handhold a 40MP MFD camera with shutter speeds of the reciprocal of the focal length. YMMV.
 
Handholding its all about angular movement, which is directly related to pixel size. Doubling resolution means you should add a half stop in shutter speed to get the same results as before (sharp or not).
 

Chris Giles

New member
Like for like at the same magnification with the same settings the P25 is visibly sharper / clearer until I up the shutter speed though?
 
Assuming insufficient shutter speeds, on average, if printed to the same size (as Shashin pointed out), both will look the same. But for sharp shots when viewed at 100% you need the extra shutter speed. So if you used to shoot at least 1/90 with the p25, 1/125 should be good for the p45.
 

Shashin

Well-known member
Like for like at the same magnification with the same settings the P25 is visibly sharper / clearer until I up the shutter speed though?
You mean display percentage? Well, then the images are not being magnified to the same degree as the image with more pixels is actually being magnified more. This is why pixel pitch in a particular format is not an issue--it is the final image magnification which is important, not how big the pixels are.

The solution is still the same, take test shots to determine your limit. No two people can hold a camera at the same limit so giving you a number is only what works for me.

BTW, you might want to look to see if it is you or the camera. Mirror vibration does not have a linear effect with shutters speeds and so a particular shutter speed may be worse than a shutter speed above and below it. And the relationship with dfocal length is not linear either--I can hold wide to normal lenses using the reciprocal rule, but that falls apart at longer focal lengths.
 

fotografz

Well-known member
Chris, I don't think you mentioned which camera is being used.

I have a heck of a time with hand-holding the focal plane shutter Leica S2 using the 120 and 180mm without doubling the focal length for shutter speed ... but can hold the larger sensor H4D/60 with 210/4 at a reciprocal shutter-speed because of the Leaf-shutter lenses and the ability to set a mirror delay.

Does your camera have a mirror delay feature? It does help.

-Marc
 

Chris Giles

New member
Marc, I've the P25 on a H1 series back and took delivery of a H3dII-39 a couple of days ago.

I have been doing the usual comparison shots etc.
 

fotografz

Well-known member
Marc, I've the P25 on a H1 series back and took delivery of a H3dII-39 a couple of days ago.

I have been doing the usual comparison shots etc.
So, how did you determine it was movement causing the softness?

I was so paranoid about the consistent slight blur with the Leica S2 & 180mm, that I did a locked down tripod test with cable release to make sure it wasn't the camera or lens. It wasn't, so I know now to use a monopod with that lens unless I can get the shutter speed up to 1/350 or higher.

Are you using the mirror delay on the H3D-II?

Hasselbladbulletin.com

This does help.

However, moving from 22 meg to almost double that does place more demand on technique if you are viewing at 100%.

BTW, when I moved to the H4D/60 I thought I'd have a heck of a time, but it isn't much different than the 39 was. The only issue was that it takes longer to resolve to full resolution when viewing at 100 or 200% in Phocus or Lightroom. At first I thought the images were slightly soft, then it suddenly snapped into sharp focus.

-Marc
 

jlm

Workshop Member
one thing i found with Phocus (and even C1) was that even after processing, the output images always looked sharer when they were opened in PS
 

Shashin

Well-known member
The difference in resolving power between a 22MP sensor and 39MP is only 33%. Doubling the number of pixels only increases resolving power by about 40%.
 

Miller

Member
Chris,

I have an H3DII 39 also. I use Phocus. The standard profile that Phocus applies at import contains only a very modest amount of sharpening (I think the standerd setting is 100, I never adjust this setting). You might have a look at sharpening applied in both your workflows, as this might influence the outcome. Perhaps you also can compare a series of shots from both backs using a tripod, in order to eliminate motion blur from the equation?
In my experience shooting handheld can give excellent results at quite long exposure (up to 1/30 with a 35 mm, 1/60 with an 80 mm). As Marc suggested, have a look at mirror delay.

Frans Rutten
 

GrahamWelland

Subscriber & Workshop Member
Chris,

This sounds like the classic pixel peep handheld high resolution issue (the D800 crowd are now running in to it). As described by the other folks, basically you have a few approaches to this 'problem' (quotes being deliberate).

#1 - produce prints just like you have with your P25 - I'll wager that they look identical or maybe sharper with the new back.

#2 - resize or visualize at the same resolutions. Which really means don't pixel peep at the same 100% resolution because it WILL be softer handheld.

#3 - shoot at 2x or 3x 1/focal length because you WILL see softness at 100% crop.

#4 - use a monopod or tripod to get the extra stability.

I've found that when I produce prints with my 60mp vs 22mp backs that in the real world everything looks as sharp unless I crop into a small section of a print or print beyond 33in on the longest axis. What you see in PS/Focus or other apps at 100% is VERY misleading compared to what hits the paper with decent sized prints. Put it another way, I've become a lot less worried about focus stacking with my IQ160 after printing more large images vs pixel peeping. What seems crap on screen (or soft) doesn't always necessarily translate into final output on paper at sane sizes.
 

dick

New member
Marc, I've the P25 on a H1 series back and took delivery of a H3dII-39 a couple of days ago.

I have been doing the usual comparison shots etc.
Tripod tests should be done with and without Mirror-Lock-Up (MLU).

If you have access to one, check the back on a mirror-free technical camera.

Hand-held tests should be repeated many times, as it makes a difference if you trip the shutter just as you heart beats... and your heart might be beating differently in a high stress situation, e.g. a wedding group, which is just when you might need to blow up one face out of a group of 12 for an A4 framed print!

The physical size of the lens, how you hold the camera, additional grips etc. can have an effect.

I have a Novoflex 640mm (35mm film) lens I can hand hold at 1/125 (using Agfa CT18)... lying on my stomach, using the pistol grip and shoulder grip and winding the strap round my elbow like some rifle shooters do... this lens is also inherently stable, as it is not a telephoto, and is 640mm long!

I rarely use my H4D-60 hand-held, even when I am not using the 300mm.
 

fotografz

Well-known member
All good advice.

One other thing I adopted was faithful use of a good hand strap. I use a Camdapter strap with a dual lug Arca QR so I can also attach a shoulder strap. I do shoot the big camera hand-held without support more than with it. It is just the nature of the work I do ... however, in those cases, I'm willing to accept that it may not be retina slicing sharp @100% views ... so if the intent is razor sharp images, especially with the 150 or 210, I know to break out the monopod or tripod.

Camdapter - The Hand Strap

I set up my mono-pod to make it as fast and flexible as possible to encourage use rather than making it a PITA. I opted for the RRS HD mono-pod head with ARCA QR that makes flipping from landscape to portrait almost instant, (note: do NOT get the QR lever type, get the one with screw knob clamp linked below)

http://reallyrightstuff.com/Product...&desc=MH-02-Pro:-Head-with-Indexing-Pro-Clamp

I also selected a HD mono-pod with QR fliplock levers so I can swiftly adjust height ... or fold it up in one quick motion to move from one location to another. I have the need, the need for speed! :) I'm using an inexpensive Benro C49F Carbon Fiber, and rarely use my Gitzo carbon fiber anymore because it is too slow to use.

Benro C49F Classic Carbon Fiber Monopod C49F B&H Photo Video

All these little things add up to much sharper images and aid in tightening down technique to extract as much of the resolution for sharpness as possible.

However, if you also shoot spontaneously hand-held, and it isn't razor sharp, you still reap the benefit of smoother tonal gradations inherent with so much data being captured ... and typical prints will look plenty sharp when printed ... something that ALWAYS surprises me ... so take care sharpening on screen as it can get to crispy looking in a print. Been there, done that. :rolleyes:

For example, here is an impromptu hand-held portrait I grabbed while doing a family "generations" shot given to the little girl's mother for Mother's day. I was mostly using lighting and doing more controlled stuff ... but also did some ambient hand-held quick portraits here and there during the outdoor session ... do you think the Mom cared that the eyelashes are a little soft on her left eye when viewed at 100% on screen? ... and her Mom is a professional photographer BTW.

-Marc
 

dick

New member
All good advice.

I do shoot the big camera hand-held without support more than with it. It is just the nature of the work I do ... however, in those cases, I'm willing to accept that it may not be retina slicing sharp @100% views ... so if the intent is razor sharp images, especially with the 150 or 210, I know to break out the monopod or tripod.

-Marc
Hi, Marc...

I would have thought that the H4D-40 would have been a better option, as it works better at high ISO?
 

fotografz

Well-known member
Hi, Marc...

I would have thought that the H4D-40 would have been a better option, as it works better at high ISO?
That is true Dick, and I did have a H4D/40. However, I don't have any issues with shooting the H4D/60 at ISO 400 or 800 either, so the 40 just gave me a stop more ISO to work with. Plus, I like the IQ of the Dalsa 60 meg sensor for people work.

The notion isn't necessarily trying to extract all the resolution the 60 can provide for everything I shoot. I'm content to accept some compromises at times when the subject calls for more spontaneity, which the H4 camera is quite able to provide. An 11 X 14 print from such a huge 645 sensor and 60 meg hides a lot of small imperfections ... and even with some movement looks just as sharp as an 11 X 14 print from the smaller crop frame sensor.

Frankly, I use the Leica S2 for the type of work I used to use the H4D/40 for. Now that Leica has introduced a H to S adapter, I can also use my favorite HC lenses on the S2 either as leaf shutter, or as up to 1/4000th focal plane ...which will bring new fun working with the HC100/2.2 wide open in bright conditions :thumbup: It's all about the glass.

That H to S adapter was simply a lucky break :)

-Marc
 

Chris Giles

New member
Thanks for the tips guys, I'll implement them over the next week or so. I think it's also getting used to the back and respecting their differences. I've not shot anything larger that 22mp before.

I am surprised by how good the P25 Tiff files look in Phocus, and how good the Hassy 39 files look in Lightroom (The same as Phocus, just with less corrections available).
 
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