Exposing on photo paper - silly idea ?

[daveh]

Berndt, I have two 'bridge cameras. Panasonic FZ1 & FZ5. The FZ1 is only 2mp, the FZ5 is 5mmp with a bigger zoom range. I would have to look up if I am correct but I think they are 10x and 12x respectively. Both have excellent optics and give great results. Both have quite small displays and rather grainy EVFs. The recent versions are much improved.

I have to say I don't mind an EVF as a viewfinder. I do prefer a nice big optical bright-frame finder, as on a rangefinder, or a 1:1 SLR viewfinder. However not having the bouncing mirror is good - vibration and noise.

Dave.

[Berndt]

Back to the original topic, I finally had some time for doing some more tests. Photo paper is pretty light sensitive. Not a bad thing ... if I would have a decent shutter, but counting seconds could be critical ... at least at daylight.

A quick shot on my roof ( not worth posting here though ) at bright sunshine and I needed to close the lens completely down to F:64 for finally getting a well exposed picture. Exposure time: a little bit less than a second, I guess, because I tried to open and close the lens manually as fast as I could.

Wanna try to test the "limits of resolution" tomorrow ( first with the smallest of those three cameras, because this is already set up ). We have a small skyscraper in the neighbourhood. Not really one of the highest in Tokyo, but already a nice view from there.

Also loaded some photopaper in another small plate camera, which has a working shutter. We'll see. I actually like the look of photopaper. Very contrasty even I choose a pretty low contrast paper.

[mickeyobe]

berndt,

Now is the time to pile on filters including neutral density, colour and a polarizer. to substantially increase exposure time.

Two polarizing filters stacked can be turned to almost entirely cut out the light.

Mickey

[nikonbob]

Looks like photo paper is about iso 6 if in normal sunlight you need 1 sec and f64. At least that is a good starting point.

Bob

[Berndt]

Here finally comes my first test picture, taken from a high building in the "neighbourhood". Unfortunately, there has been double window glass, which might have lowered the quality, but the result is still impressive, I think and the perfomance of photo paper promising.

Exposure time app. 1 sec at F:45, 180 mm Fujinon lens on 4 3/4 x 6 1/2 inch B/W photo paper, scanned on an Epson GT-S620.


Wideangle view on Tokyo/Shinjuku by bokuwanihongasuki, on Flickr

For checking the resolution, I also scanned an enlargement/crop of one singe house, distance app. 5 km from the camera:


Enlargement 1 - 4800 dpi scan by bokuwanihongasuki, on Flickr

And here comes the largest crop, showing the limits ... but more of the scanner/lens/weather than of the photo paper, I think. My cheap scanner can "only" do 4800 dpi and it can not be clearly said, if we are reaching the limits of the camera lens or optical unit of the scanner here.


Enlargement 2 - 4800 dpi scan by bokuwanihongasuki, on Flickr

One day, I like to use my largest camera ( 10x12 inch ) for taking a picture of Tokyo from Mori Tower, which is the highest building in Tokyo providing an open space view from the top. 10x12 inch would provide an even six times higher resolution than on those ones and of course, the weather should be nice then

However ... for that, I need to solve another problem first. My largest camera has no lens I want to use the Zeiss Tessar 210 mm if possible ... but how can I mount it ? It has a 6cm screw mount and the largest camera has the same type of mount but with a diameter of 8.5 cm. Are there adapters ? Or should I better try to get a suitable lens for this mount/camera ? Any good ideas on that ?

[mickeyobe]

berndt,

You did it. Your results are impressive.

Is the Zeiss Tessar 210mm able to cover the full 8 x 10 area? This is most important.

Does your camera have a removable lens board?

They are easy to make out of good quality plywood of the proper thickness, often 1/4 inch.
Cutting a hole with a circle cutting blade just slightly smaller than is needed and finishing it to size with a file is not too difficult.
If the lens has a flange with holes for screws you are well away. If not and if you can't find a suitable flange you can size the hole so the threads on the back of the lens can be screwed into the lens board cutting its own threads as it goes.

All this I have done successfully and if I can you can.

Mickey

[Berndt]

Thanks Mickey, I'll try that !!! If the Zeiss Tessar 210 mm covers 10x12 inch ? I don't know ... but I might find out if I just provisional mount it in a simple way.

BTW ... I accidentally found out more about a possible maker of my cameras. The largest one and all ancient shutter units are marked with the name "Hansa". The only thing, I could found out though is the fact, that a precurser of the company Canon used this brand name ... but I couldn't find any information if large format plate cameras have ever been released under this brand name.

That obviously has been the case, because I own them ... but I can't find any further information, which could lead to an exact date of release. Considering, that it came with the Zeiss Tessar ( which could have been purchased later of course ), I would date the camera at least to the early 30s, but the brand name "Hansa" has been used already in the 20s as well ( even not by Canon and I can't find any evidence if for large format cameras ).

[mickeyobe]

berndt,

I don't know if this will be of any help.

I used to own a Hansa enlarger. So they were making photo equipment.

Mickey

[nikonbob]

Congratulations, that is looking extremely promising. Can't wait to see what the 8x10 can do.

Bob

[colray]

One of my projects is ..making a 5x4 view camera from recycled materials .. the camera is a long way from being finished.

At the moment I'm not sure if I should go for Monorail or Folding Flatbed and how much bellows extension do I need.. I guess the easy way is make a mock-up and do some tests.

So bolt the parts on some scrap timber and make light tight with a garbage bag.



Test using paper negative f12.5 30 sec exposure + yellow filter Foma paper and developer.. plus a bucket load of contrast added in PaintShop Pro.

The lens used is Russin and over 70 years young.

[nikonbob]

colray

Geez, I had forgotten you had that project on the go. You make it look and sound so easy but I bet it wasn't. It must feel really good to have gotten that first photo. Looks pretty good from here. Will you make your own bellows or have them made?

Bob

[colray]

Hi Bob haven't made the belows yet.. but have made a couple of tests so far.. just can't get it right.
I have been very slack and haven't posted much of late.. but have now found the thread and done some updating.
Colin

[mickeyobe]

Roy,

Please keep us posted on what looks to be quite a challenge.

Your photo proves you are on the right track.

Mickey

[Berndt]

Looks cool. A selfmade camera. Wow !!!

[nikonbob]

I don't know if you guys have seen this www.ilfordphoto.com/products/product.asp?n=75&t=Photo+Accessories+%26+Equipment . The camera is interesting in itself but it comes with Harmon Direct Positive Paper made by Ilford. Here is a link to the tech sheet for it www.ilfordphoto.com/Webfiles/20108271643311748.pdf . Interesting to note that the paper is iso 3. Just thought it may be of some interest.

Bob