chuck_pere

Small, light and fairly cheap is the 150 G-Claron. I use mine for 5x7 all the time. Coverage increases as you stop down and I normally use it around f32. Downsides are dark glass at f9 and single coated. Coverage spec for this lens is usually given for 1:1 but I'd assume around 85 deg at F45 for infinity.

So what are these early f7.7 lenses, tessar or four-element air spaced dialyte? I always assumed they were dialytes.

One developer I like in high contrast is PMK Pyro. Works Ok with either HP5 or Delta 400 in my experience. You can buy premixed liquid kits so it's pretty easy to use.

Thanks for the info Steve. I seem to have lost a great Pentax 67 lens information site when AOL recently closed their web pages.

For the 55mm f4 are the 6x7 and 67 versions identical optically? Looks like some mechanical differences.

I've seen the problem on mine. It is intermittent so I really haven't done any troubleshooting. Just ignored it as I was using the camera in the field. I would try a battery change if you can verify a continuous problem so that you can see if the change helps. Or even just remove and install the batteries. I bought my camera used and the problem was seen after a couple years of use. It does knock the hell out of the resale value so if you just bought one with the problem I'd advise a return or ask for a large refund. Maybe 30% or so. I plan on just ignoring my problem until it gets so bad it hinders the camera operation. No planned sales for me as this is a great camera to grow old with.

Following some advice I read some time ago I started adding a couple cap fulls of 91% alcohol to my Photoflo mix. That and using only distilled water seems to work for me.

I believe that my Bessa (late pre -1 model) had 90mm negatives. They were larger than the 23c carrier which is 82mm. My old Rado 120 holder for 9x12 measures 83mm. Seems like my Graphic 23 roll holders are close to that. They definitely work with the 23c carrier. Bessa was the odd one out and needs to be cropped to use the 23c carriers. Need to build a special carrier for it, file standard carrier open or use a 4x5 glass carrier if you want full frame.

Will the rear elements fit into the 2x3 Crown? Guess you could do the screw/unscrew routine to mount it.

Why not just get a pinhole for your DSLR?

Seems like a lot would depend on the aspect ratio of your output. If you enlarge holding the long side to the paper size you would only go from 6cm to 7cm (nominal). Cropping to the short side would give a much bigger improvement. I like the 645 aspect ratio so for me going to 6x7 might not be a huge gain. I need to go to 6x9.

There is an active large format group in the area:

http://www.midwestlargeformat.com/

 

They usually meet once a month for outings. I'm sure that people in the group would be glad to help you with any questions. Not exactly a formal workshop if that is what you are after.

Not sure if these are being built anymore but you could ask:

http://meteredlight.blogspot.com/

 

If they aren't being built the used price will probably be very high due to the supply demand problem.

I've been using one with my 5x7. Covers 5x7 OK and seems like a nice sharp lens. Also good for closeup work. Very small and light. I would say that if you are using 4x5 and don't need very small size or huge coverage stick with one of the regular 150 f5.6 plasmat lenses. These really aren't that much larger and 5.6 makes viewing easier. Well another case for using one is if you do a lot of closeup work.

I like my Tamron 105 f2.5 which I got in the early 70's.

Another quick way to look at focus is using a piece of magic tape. If I recall correctly the Bessa didn't have a way to adjust the infinity point on the lenses like an Agfa. So probably someone screwed the lens in at the wrong point. Been there and done that. I had to find the right point by trail and error.

I'll add the obvious. The focus is done by estimating the distance and turning the lens to align the number with the pointer. So you have to be pretty good to do selective focus work.

 

Another thing I like to do is always wind to the next frame after opening the camera not after the picture is taken. This really seemed to help with my dust problems.

 

I've had the same camera. It takes OK pictures. Nothing special but folders are always fun to use.

Does it have the front ring you turn to vary softness? If so search on the large format forum as they have talked about how to use the ring and focusing. The problem is do you want to focus first and then set the ring or set the ring and then focus?

Are nitrate- based negatives hazardous in any way? I've heard they can start burning but never heard of anyone who has had a problem.

2 1/4 x 3 1/4 sheet film is slightly smaller than 120 so it will not fit on 120 reels. I use an adjustable Nikkor sheet film tank to develop it but that tank is rare and expensive. I have heard of people folding the film and using rubber bands to hold it. They put this into a standard reel type developing tank (no reels). You might try to seach for "taco" method for more info. Another cheap option is just use a Yankee sheet film tank. They should be cheap but have a bad reputation for agitation problems. But should be fine to just try a couple sheets as long as you have complex subjects without large areas of tone.

 

Could someone explain the facts on RB-67 backs. Do all back series work without modification or only the first (non pro-s) kind. For later backs what did you have to do for use on a Century?

You might try a minimum agitation technique with Pyrocat HD. When I did it I agitated for the 1st minute, 1 invert per minute till 4 min and then 1 invert per 2 min after. I just pulled that out of my you know what so do a search on minimum agitation here or APUG to see how the experts do it. I used Efke 25 9x12cm sheet film when I did it.

Do you always have the problem with only the top reel?

A couple other places to check with are Midwest Photo and KEH. I don't see anything really expensive in your group. The Ikeda would have the most value. But the total would be under $1000. For a quick sale just get an estimate from the store buyers and sell to the highest one. If you want to work for a couple hundred more dollars sell the pieces individually on Ebay.

One major cost problem for 5x7 is the price of used holders. They are much more expensive than 4x5. A couple new brands from China are coming out but they are not cheap either. So don't forget to factor that into your cost comparison.

 

5x7 is a little bigger and heavier than 4x5 but IMHO no harder to use. If fact the bigger ground glass may make things easier to see.

A good 8x10 lens is the Fuji f6.7 250mm. Coverage is listed as 398 mm. I've used mine on 8x10 with no problems. They have a good reputation, are small (67mm filter size) and are fairly cheap. Downside is that they are only available used and are single coated.