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View Full Version : Digital back on 6x7 and 4x5 ?



evgenyg
10-Oct-2008, 09:49
Hi.
here is my first post here.

1. From my experience a 6x4.5 film (contax) scanned with Nikon 9000 is equal a 22 mega pixels back. Is there any reason to use a 22 mega pixels digital back on a larger Mamia RZ67 IID? Why a digital sensor will outperform a 6x7 film?

2. I have a Sinarback 54M digital back attached via adapter to my Contax 645.
How to use a moveable back (Contax 645 moveable back called Widepan made in china) attached to Sinar P2 4x5 camera? I'm completely new to moveable backs, are they worth the money? Is this back for still life subjects or whatever else?
Is a 4/16 shoot digital back a better buy for still lifes, such as Sinarback 54H?

Thank

Gene McCluney
10-Oct-2008, 10:06
To fully utilize the functions of your Sinar 4x5 you need a scanning back, such as a Betterlight (brand) one. this has an image area very close to full 4x5. Since it is a back that "scans" the image area, it must be used only for still-life shots, and under so called "hot" lights (continuous lighting, no flash), but can deliver results far superior to the bayer-pattern digital backs when used within its parameters. The scanning backs give you full color information for each pixel, unlike the interpolated information in a Bayer-pattern back, thus the "real" resolution appears to be higher for the same pixel-count of a Bayer-pattern back. It is the "industry-standard" method for digitizing artwork (paintings, drawings, etc.)

These backs are like a 4x5 film holder. In use you compose and focus on your ground glass, then stop down and slide the back in just like a film holder, and initiate a scan from your computer-to which the back and control box are attached to.

The current versions of the Betterlight (brand) backs have a battery powered option, thus with a laptop, you can use the system outside the studio, for subjects such as architecture and still-life (no people) scenics.

Gordon Moat
10-Oct-2008, 11:24
You could do stitching with a MFDB on a Sinar (or other view camera), though ideally you want a subject that does not move (much) between shots. A bigger issue might be getting accurate focus, though you could confirm with a laptop or computer tethered to the digital back. Probably more ideal for still life or product photography.

The bigger difference between a smaller than 6x4.5 digital back and 6x7 film is in the tonality. A blue sky has no resolution, but will look smoother from 6x7 film in most situations (depending upon film). Don't forget that scanning and post processing are big factors in quality, and many times it is far easier for some people to get better results from digital backs due to a lack of post processing skills (yes, that is a criticism).

What you should really consider is not equivalents, but what you want to accomplish. If the file sizes from any medium format digital back (MFDB) are allowing you to get the prints you want, then you have no need to change or upgrade. When your current gear does not meet your needs and expectations, then look into alternatives.

Ciao!

Gordon Moat Photography (http://www.gordonmoat.com)

evgenyg
10-Oct-2008, 11:53
Thank for reply and details about Betterlight.

I never used scanning backs and continuous lighting.
Can I use halogen lamps to light small still life tables?
Is it worth to buy Betterlight for studio still ife photography comparing to current 6x4.5 scans and 22 mega pixels one-shoot backs, will I see a real difference in the final image?
Is ViewFinder software allows to set white balance using grey card similarly to regular MFDBs?

Thanks

Gene McCluney
10-Oct-2008, 11:57
Thank for reply and details about Betterlight.

I never used scanning backs and continuous lighting.
Can I use halogen lamps to light small still life tables?
Is it worth to buy Betterlight for studio still ife photography comparing to current 6x4.5 scans and 22 mega pixels one-shoot backs, will I see a real difference in the final image?
Is ViewFinder software allows to set white balance using grey card similarly to regular MFDBs?

Thanks

Yes, you can use halogen, or any other type of continuous light, including flourescent. Many people make fixtures out of several flourescent bulbs to get the light level up without the heat.

You should see a difference between a 22mp back and any of the modern scanning backs.

Absolutely, you can "click-balance" on a grey card placed at the subject for accurate color balance.

evgenyg
10-Oct-2008, 12:03
Do I need any special lens to take the advantage of the Betterlight?
Is Sinar F2 with 180mm Sinaron Digital lens Ok? (I wrote "P2" in the first message, which is incorrect. The camera is F2.)

erie patsellis
10-Oct-2008, 16:50
From personal experience, the F series is iffy with a scan back. As rigid as it may feel when locked, it's nowhere near what a P is when locked, you may be happy with the results, I wasn't and bought a P for my Phase One scanback.

Gene McCluney
10-Oct-2008, 22:14
Do I need any special lens to take the advantage of the Betterlight?
Is Sinar F2 with 180mm Sinaron Digital lens Ok? (I wrote "P2" in the first message, which is incorrect. The camera is F2.)

Any lens you can put on your Sinar will work with a scan back. It doesn't matter, and it doesn't have to have a shutter, as you don't use the shutter. If it is a good lens for film, it will be a good lens for the scan back. The scan back takes in a slightly smaller area than 4x5.

While the F2 is indeed lighter in weight than a "P" (I have a P-expert), it should work fine in a studio situation. I have used my scan back on many different kinds of 4x5 cameras, including a Crown Graphic press camera with excellent results.

For scanning, you use an infrared blocking filter on the lens, and these filters (one for tungsten balance light, and one for daylight balance) come with the scan back.

The cool thing about scan backs are the ease with which you use them, alternately with film holders. Nothing about the camera is changed, other than the filter on the lens. Normally these square glass filters are installed into a filter holder that just clips to the lens, so it can be used with various size lenses. I have even just taped it to the lens for larger lenses such as a 14" Commercial Ektar.

Lenny Eiger
11-Oct-2008, 11:03
Hi.
here is my first post here.

1. From my experience a 6x4.5 film (contax) scanned with Nikon 9000 is equal a 22 mega pixels back. Is there any reason to use a 22 mega pixels digital back on a larger Mamia RZ67 IID? Why a digital sensor will outperform a 6x7 film?


I doubt it, but even if this were true, a scan with a drum scanner would exceed it handily, and give many more pixels (to make larger prints). I get 96 megapixels off of a 35mm on my Premier, and about 300-350 megapixels off a 6x7. there's no comparison. Way past what most digital can do.

For commercial use, digital is often easier, especially if prints at larger sizes are not required.

However, when I considered the Betterlight, at 22,000 and a new Canham 8x10, at 3,000, I thought I would save myself 19,000 dollars. That doesn't take into account the cost and hassle of film and developing, of course, not to mention the knowledge required, as Gordon suggested. That's why I suggest digital for commercial applications, where you can make your money back. However, for an avocation, or for doing fine art, a great 4x5 and a lens or two can be gotten for 3-4K, and with scans will outperform any digital camera on the market.

It really depends on what you want to do...

Lenny