john_sparks1

I have a 4 shot sequence that I made with a Bronica GS-1 that clearly shows this problem. A half used roll of film had been sitting in the camera for a week or two. The subject I was shooting was a mountain ridge at infinity. I think I was using about f/5.6 or f/8.

 

The first frame (that had been sitting flat in the film gate for the week) was reasonably sharp across the entire frame. The second frame (that had been sitting bent across the roller for the week) was sharp at the left edge and got less sharp to a point about 1/3 way to the right edge then got slightly sharper again (the rollers run up and down on the GS-1). The 3rd frame was unsharp on the left edge but sharp on the right. The 4th frame was sharp across the whole frame.

The unsharpness was enough that the 2nd and 3rd frames were totally unusable. All shots were at infinity and I didn't change focus between shots (besides the difference in sharpness across the frame ruled out a focus problem).

 

Now, I always shoot an entire roll within a 1/2 hour or so and haven't seen the problem again (at least not to the point of having unusable negatives).

 

I tried a similar experiement with a Horseman 6x9 back. This back has rollers that are 2 or 3 times larger diameter than the small rollers in the Bronica. I couldn't see any unsharpness between frames when comparing a 3 frame sequence when a half used roll of film sat in the back for several days.

With my GS-1 under normal operation, the mirror goes all the way up on mirror lockup. You can see this if you remove the finder, but leave the lens and back in place. If you remove the back, mirror lockup only raises the mirror about 2/3 of the way. It goes up the rest of the way when you release the shutter. Don't know why it works this way. Try this with your ETRsi. I don't think you have anything to worry about.

Could you give some more details about the Toyo or Horseman 6x8 backs? I've only seen 6x7 and 6x9 (note that 6x9 is actually about 56x82mm and gives 8 exposures on 120, 6x8 backs are about 56x76mm and gives 9 exposures on 120). I'd really like a 6x8 back for my Horseman. Anyone used the RB back on a view camera?

As far as I've been able to determine, the only 6x8 (9 exposures on 120) cameras available are made by Fuji. The 680 that you mentioned and versions of the Fuji rangefinders sold in 6x8 format in Japan only. I think that's unfortunate since I really like the shape of 6x8 negatives (actually about 56mm x 75mm), 6x7 seem too square and 6x9 too long, especially on verticals. The 9 exposures also fit nicely on contact sheets, unlike 6x7.

 

There are a number of 6x9 (8 exposures on 120) cameras, several of which have movements and most 4x5 view cameras can take 6x9 roll film backs. For something that is small, easy to carry and quick to set up, I really like my Horseman 6x9 technical camera. Mine is a 980 but the 985, VHR and VH are fairly similar (the VHR and VH have rotating backs and all but the VH have rangefinders so that they can be used to some extent hand held, only the VH is available new). I believe the Silvestri only has shift, but I've never seen one and may be remembering what I read about them wrong.

I recently bought a used 2003 that had what I think is the same problem. In my case, the part was still mostly attached to the back of the mirror. It was attached to the edge of the mirror closest to the film when the mirror is up (the top edge of the mirror when you are looking at it through the back of the camera with the mirror down and shutter open). I was able to stick it more firmly on the mirror and it hasn't come loose again since.

 

The piece, in my case, was flocked on one side (glue on the opposite side). I believe that it is some flocking material to reduce flare in the camera body during exposure, especially since it almost butts against the film.

 

It may be worth the risk of more flare for the benifit of never having it come loose again during some important roll of film! If you hear from Hasselblad, please post or email their reply.

An update on Accent photo lab. My experience with them has been with 35mm machine prints, custom prints from 120 and reputation from others. I just tried to drop off a roll of 120 for process and proof today and was told that they don't do machine prints from 120. My choices were a contact sheet or $4.00 per print custom prints. I will be taking my 120 processing somewhere else.

Like the previous response, I've used both Shewmakers and Accent (I've only used 120 so don't know about 220). The last roll that was processed at Shewmakers had a scratch and some chemical blob on the negatives. I know they are trying hard to get back to their previous high standards, but they have new lab personel and are having some teething problems. All their roll film processing is at their 19th street store (630 N. 19th, 520-9970) so you get the fastest turnaround if you take it there instead of one of their other stores.

 

Accent does a very good job. I had some negatives printed at both places for comparison purposes (machine prints from 35mm) and the Accent prints were somewhat sharper, color was good and fairly similar from both. Accent cost more. You can check out Accent photo at www.accentphoto.com.

 

Both print on fairly contrasty Commercial/mass-market papers not portrait papers (Accent uses Fuji Crystal Archive and I think Shewmakers uses Kodak Royal). I don't know if Accent will print on lower contrast paper. I know Shewmakers will not.

 

I'm not sure I'd call either one a pro lab, but Accent is closer than Shewmakers. The only "pro" lab in town is Gerards, just a couple of blocks from Accent on 981 Elkton Drive, 594-0848. They do a good job with film processing (they use dip and dunk machines), but I'd only consider their machine prints as proofs (Accent's prints are better). They are overagressive cliping on to sheet films for processing, so you end up with marks well inside what I would consider the image area (not a factor with 120, of course). They will do custom printing but are surprisingly inflexable in how much work they are willing to do to make a custom print. I prefer accent.

 

If you need a real pro-lab, you should look in Denver (about an hour drive to the north). At least one or two do daily pickup/delivery to Colorado Springs.

I use medium format (Hassy, 6x7 Bronica, 6x9 Horseman) and 8x10 and have used a lot of 4x5 in the past. I pretty much only use B&W (color film with it's diffuse dye clouds seems to be less affected by negative size than B&W to me).

 

Anyway, 16x20 prints from 8x10 negatives are definately sharper and hold better details than anything printed that size from medium format.

 

However, using Agfapan 25 or Ilford Pan F+ in 120 (films not available in sheets) and enlarging to 16x16 from Hassy or 16x20 from 6x7 and comparing to 16x20 prints from 4x5 TMY negatives (my usual sheet film choice), the results are quite close. Using something like Delta 100 (in my opinion, the sharpest B&W film available in 4x5), there is a small edge to 4x5 over Agfapan 25 in 120 in a 16x20 print. Larger prints make the difference more obvious and any technical problems are much more visible in the smaller negatives (not quite the right exposure or development, for example).

 

I've pretty much stopped using 4x5. If I need something more portable than 8x10, I'll use medium format. The extra hassle of dealing with sheet film isn't worth the minor difference in my final prints.

 

The biggest problem I have with most medium format is getting enough depth of field without swings and tilts.