my Full Frame camera is 35mm film

Fortunatly we've had 35mm around for longer than digital, and while I really DO like my micro43 cameras I am under no illusions about it and know that good old 35mm full frame (there was half frame you know, such as the Olympus Pen F series) exceeds it in many ways (though convenience isn't one of them).

At about the time when digital cameras (my main snapshot cameras for 15 years now) were good enough to use as a reasonable substitute, Film Scanners were expensive and their use was poorly understood. By the time that good scanners were at reasonable prices and systems like Noritsu's 35mm development / scanning process machines were around it was too late.

For the enthusiast picking up 35mm gear at bargin prices, and for those pulling out their old images, the quality you can get with a good scan rivals the best of the current Full Frame digital cameras (like the Sony A7 or any of the Full Frame Canon / Nikon cameras). Especially if you don't have shit hot lenses.

I was going through some older shots I took in Tokyo back in about 2002 and liked this one of a temple just up from where I lived

Its a good 20 Megapixels.

I took it with my faithful (still running fine) EOS630 with an EF24 f2.8 lens (still running fine too).

So lets have a look at some details ... at pixel peeping levels ... from over there on the left ... just under the roof

then the gutter above it ...

moving over to the right hand side:

and lastly one from the middle:

Which makes it clear also (judging by the reflections in the windows) that I could have focused a little bit closer than I did (instead I relied on the infinity "stop" on the lens) and the rope would be sharper .... when magnifying this much (which is what a good scan does) the DoF assumptions many people make on 35mm (like what's on the lens barrel) are inadequate.

So, all in all I'm not about to stop using my digital camera but I recognize that its got its place and that there is still a place for 35mm for me (especially for 4 day hikes in -15C where batteries freeze).

Enjoy

old power - battery adapters to power old cameras (OM-1)

I happen to really like my OM-1

Its a great camera, but it has a significant problem in this day and age; being a rather old device its hard to get power for it.

You see since it was made there has been quite a revolution in both electronics and enviromental (or is that enviro-mental) thinking.

Sadly as most people are unable to be responsible with batteries the uber reliable mercury battery it used is discontinued.

Now luckilly there are a few stalwarts who are serious about these cameras (should tell you how bloody good they are) and have put some thought and effort into keeping the things breathing. One very informative page on this topic is here. So essentially I needed to replace the PX625 battery with something else, in this case it is the common Hearing Aid 675 Zinc Air Battery. As described on Rick's page the discharge voltage curve of the Zinc Air is very similar to the original Mercury type.

Anyway, lacking the o-ring mentioned in his article (and the wire) I first turned to a bit of cut to length cable tie. As long as you get a cable tie of ~2mm diameter (as suggested in his fine post) this can be used in the battery compartment to solve the size difference.

Not wanting to "cheap out" on my OM, I decided to look around and see what might be available. Fishing around on eBay I came across a Japanese seller making a high quality machined part. His name is nobbySparrow, and in the 'invisible hand' tradition of market knowledge I thought I would write up his product (as I have others I've bought).

The product is essentially a 'metal cup' to hold the 675 battery to allow it to be placed into the battery compartment of the OM-1

The smaller battery just slips into the compartment and then the whole thing goes into the camera.

It looks a little 'loose' by today's modern tight manufacturing standards, but the way that the OM-1 battery hatch is designed actually holds it in firmly.

you can see the ridge around the cap above.

So there you have it, a simple, inexpensive and well made adapter for the battery.  I paid US$12 for two adapters, its nice to have two in case I loose one. So for essentially $6 each I have a smooth and simple fix for my OM-1 battery needs. Oh, and a pack of 6 batteries was $2

 

So now I can just go out and take pictures with my OM-1 and not need a handheld light meter or fiddle around at battery change time.

And take fine pictures it can; especially with Negative in contrasty conditions it not just rivals digital cameras it exceeds them.

and a detail segment:

so its a small investment to keep a fine and functional photographic tool functioning.

Thanks nobbySparrow :-)

G1 (or any smaller sensor) and wide angles

I happen to like wide angle lenses, back when I used 35mm film I usually liked 24mm or (used carefully) 21mm. The first thing I found when I picked up digital cameras in the year 2000 was that I didn't like what options existed for wide angles. To this day the options in wide angle for 4/3rds are quite restricted ... I can think of only the Panasonic 7-17mm and the Olympus 9-18mm lenses.

So in this article I'll compare the same angle of view on full frame and the 4/3rds. I say angle of view as focal length is really a meaningless measure unless you clearly understand the relationship between that and format ... not everything in the world is 35mm you know. Thus we are talking about a wide angle of view in this article.


Before I moved over to the Panasonic G1 I was a Canon EOS user for many decades (well since about 1990 actually). I have owned the EOS 10D and 20d but I have not owned a full frame digital, I of course still have 35mm bodies lying around.

One of the things which is true with smaller sensors is that to get the same angle of view you need a shorter focal length lens.

So looking at the diagram to the left to get the same 73 degrees angle of view the smaller sensor (yellow line) needs to be much closer to the lens than the larger sensor (blue line).

This means that for the smaller sensor you need a much shorter focal length to get the same angle of view.

So more or less if you use a 21mm lens on your 35mm camera you need a 10mm lens on the 4/3rds.

If all things were as simple as this then there would be no problems, but they of course are not so simple. For a start the difference between the 35mm frame and the 4/3rds frame means that to get the same angle of view you need about 1/2 the focal length (again since the aspect ratio is different its not exactly that, but lets leave this simple).

As it happens designing a zoom lens of such short focal length that will work on a digital camera is not simple and is as such more complex than a 21mm on a 35mm. This means that your lenses may be more expensive.

I used for this experiment an old Olympus 21mm f3.5 lens on the full frame and an Olympus 9-18mm Zoom for the Panasonic 4/3 camera. As I said I don't have a full frame digital camera, so the full frame images are scanned 35mm film. I used 200ISO negative. Actually this turned out to be an interesting basis for also comparing the latest digital with 10 year old film based digital photography (yes, I call scanned film digital ... no ni).

So firstly lets have a look at the overall image from the 35mm:



Next (not quite the same angle I'm sorry) the image from the G1.



Looking at the overviews I think you'll agree i got the colour quite close ... to get the same look I started with the RAW file and processed that significantly using a few steps which I've learnt. Its interesting to see how the shadow details are similar on both but the digital still managed to have trouble with the white of the birch trunk. That might look ugly in printing if your not careful.

I still find that negative film has much better recording capacity when you need to deal with strong light. I certainly found this in my previous explorations with my 10D and 20D, but its interesting to see that nothing has changed, and even careful use of RAW files does not stop this.

Secondly I am immedately struck by how much nicer the background "bokeh" looks on the 21mm lens ... to me the 10mm looks harsh and distorted. The little Olympus 21mm is a sweet lens for sure.

Now onto the detail. Below is a screen shot of the images at 50% res on the screen. I find this a useful determination of how a print will look at close inspection. Bear in mind we're essentially looking at a print which would be 34.0 x 25.5 cm ...


Its really close isn't it ...

If you think that the top of the mushroom is looking a little fuzzy, thats because the 21mm lens has a shallower depth of field at f5.6 than does the 10mm lens, and the focus was 'just slightly' ahead of the mushroom ... need to be careful in focusing manually!

But depth of field will be effected as the important criteria there is the diameter of the aperture, not the f-stop. Please take a moment to read my article here to confirm that for yourself.

So to have an 10mm lens giving the same DoF as I get with my 21mm @ f3.5 I would need around f1.8 The Olympus 9-18 zoom is simply not that bright, its f4 so to get the same DoF I would need to stop the 21mm down to f8 From this I'm sure you can see that the "look" of images between the lenses focused on something close will not be equal if we get the f-stop the same.

I thought I'd try another angle, one that requires distance this should eliminate DoF and get rid of the significance of any Bokeh.

Full Frame



G1



I think you'll agree that aside from colour matching them (close but no banana) the images look more or less the same (well and aspect ratio).

Differences in colour rendition is significant though as I think that the digital image (lower one) handles the subtle grades in the sky better than negative does ... this is something I've found before, that digital is better suited to capturing subtle shades than Negative is, and that negative works better when you have a wide dynamic to capture.

Looking at the detail there is surprisingly little in it. There is of course no difference between Depth of Field (as infinity is all thats in the focus here) but its also quite significant that the film scanned with the Nikon LS-4000 holds so well against the digital (or is it that the digital does so well against the film? you pick).




So, this cements in my mind that larger format (sensor or film) works best for wide angles. I would very much like to compare a 5D or other full frame sensor camera to the G1 as I think that it would be just fantastic. On the other hand the G1 costs so little that if you pop that onto your 300mm lens then instead of needing to buy a 600mm lens on a full frame camera you'll get better wildlife shots, this for example was a legacy FD series 300mm lens on my G1:



Bang for buck that's cheaper than buying anything for the full frame.

My summary is that

• If you want wide angle and want nice Bokeh then use a full frame camera and a 21mm lens
  
• neg has better handling of sunny contrasty conditions,
• wide angle on the G1 (small sensor) is ugly compared to full frame, but telephoto on the G1 or APS sensor is advantaged
• unexpectedly the G1 pulls very close to the 35mm in outright resolution (which means that the main advantage of digital is still workflow and materials costs)
  
• if desiring of shallow depth of field, when using lenses wide open aperture favors larger formats like full frame (but 6x7 and large format really needs movements to correct for and is harder to manage)

Testing LS-4000 with Stouffer Stepwedge

Now that I have a LS-4000 in my home I thought I would apply some of the same testing that I have previously used on my Epson flatbed scanners. I used the FH-3 holder to hold a Stouffer Stepwedge and scanned it in sections to see how the scanner responded to levels of denisty.

I was stunned how it ran out of grunt in ability to penetrate the dark areas. I noticed how sensitive to the 'clear' area of the wedge it was so I popped a little bit of analog gain into the scan (0.8 actually). I did this to hopefully extend the dynamic range into the dark areas and bring the white areas up to begin clipping at "film base".

Cutting straight to the results it is not only not good, its actually surprisingly not good.

This is the result of a scan with 0.8 of analog gain applied to the master gain.

I have plotted a Log₁₀ graph of the results in red (as this is how scanner responce needs to be measured for photographic purposes).

It seems to have made a strange change to the "linearity" of the scanner with a marked step occurring at about step 13.

Its strange that both parts remain more or less straight with a deviation in the middle.

Further, the 'blooming' of the scanner is apparent in the darker areas (note the small intrusion of one of the "frame" supports in the FH-3, this shows that the depth of black is not fully reached even though the ability to discern graduations is substantially impaired).



out of interest this is the result from my Epson 3200, and no blooming is evident in this.



so ... this makes the result from the Nikon particularly scary. Feel free to compare this to the results from my Epson 4990 scanner here.

Note: this effect of blooming is also apparent with x8 oversampling, so it is not just a digital noise issue.

I also thought it was worth mentioning that not only is there substantial bloom (clearly visible here) but that altering the analog gain disturbed the levels of RGB too. Looking at the RHS of this graph you can see three peaks, this is the places where Red Green and Blue have moved up towards 255 but clearly unevenly.

So, without careful profiling using the analog gain on this scanner to 'punch into dark areas' will result in strange colour shifts. I advise use with caution.

I left this section 'zoomed in' to show just how much blooming results in the transition from dark area to light area, it is significant.

---

Addendum

I was asked some additional quesitons about this so I have repeated the tests and included results for 0 analog gain.

NOTE: rather than wait over the weekend I've disassembled the scanner and sure enough the mirror was rather filthy. So a quick clean with windex and a cotton bud (removing the mirror of course) later and its now performing well


My method was to scan with the scale set as linear from 0 to 255, the scanner software is set to put the data into Bruce RGB, so after scanning this profile was assigned to the data to ensure that the results are correct. As the wedge is so long, I had to scan it in 3 sections. To perform this I needed to

• insert the wedge strip into the FH-3 holder
• disable any preview or focus on insert
• scan each step without prescan or preview

some overlap was possible in scanning (as it is manually fed) so I can confirm that (for instance) the values of step 4 (and the clear part of the step number) were consistent from scan to scan.



The results (data first) include the stand deviation of the values in the selection swatch. Standard error is calculated as the percentage of standard deviation to the median value (not, I use median in this testing not mean).


It seems to indicate that the error is getting quite high as the values go above 13 on the stepwedge. This needs to be taken into account when assessing how effective alteration of the image with curves will effect colour accuracy or noise in shadow details. Now the graphical view




seems that the linearity step at about 13 is still there