DPR Forum

Welcome to the Friendly Aisles!
DPRF is a photography forum with people from all over the world freely sharing their knowledge and love of photography. Everybody is welcome, from beginners to the experienced professional. Whether it is Medium Format, fullframe, APS-C, MFT or smaller formats. Digital or film. DPRF is a forum for everybody and for every format.
Enjoy this modern, easy to use software. Look also at our Reviews & Gallery!

Does your Contax RX underexpose

So Guys,

If you were using an exposure meter, what would you dial in for Velvia - ISO40 or ISO50? And how would you then translate that into your camera? Is it therefore possible to calibrate your camera against a handheld meter (assuming that was correct!!)?

Cheers, Saras
 
It's an interesting debate about film speeds, particularly for positive film (I use my beloved RTSII for black and white negative film and never worried about this in the same way because there's so many variable factors).

One of the things I mentioned in my first post was that, whatever the "real" film speed, and whatever the calibration of the camera's meter, my first experience of Vevia 100F (not classic Velvia 50) is that it was faster than Provia 100F. Now that's based on one roll of film only, but they were all processed by the same high quality professional pro-lab.

Anyone else noticed the same?
 
FYI

if you find a typo in your posting, you can correct it within 30 minutes after posting it the first time. You do not need to send a second e-mail out.
 
Hi Mike

I agree with all your points about possible causes that could explain why I think my ST and AX "underexpose" compared to my older cameras.

I don't (or didn't) really see it as a "problem", it was more "a curiosity" at the time. The answer I got from Kyocera was even more curious!!

The fact that some others had noticed it, some had suspected it, or some hadn't even thought about it until I mentioned it, and then said "Yes, I think you are right!", lead me to wonder if there really was a "trend".

I guess the reason I asked the Service Manager about this, was ... a) to see if there really was a reason, or was it just our imaginations! .... and b) ... because I could! (being in touch with Kyocera frequently regarding Club activities.)

The answer he gave (in previous post) surprised me! It was over 5 years ago, so I don't remember his exact words .... just that I remember him implying that "they" had altered the exposure and that his explanation was that it was to give a "more saturated" look.

I now wonder if the "alteration" was simply a consequence of using (for ex&le) different meter sensors or different electronics in the "newer" cameras, compared with "older" cameras, and maybe not a case of "let's alter the exposure". I doubt that we will ever know for sure.

Still, it's an interesting debate, and I would welcome other's opinions if they have owned both older and newer Contax models.

Cheers, Bob.
 
John, You do not say whether you were using your RX on spot or centre-weighted setting and what lenses. When I was on a yacht on the Mediterranean this summer with often difficult lighting conditions, light on water etc. and using Velvia, I did get some over-exposing when using centre-weighted and wide angle lenses, particularly a fish-eye (probably best to ignore that one since it was a Zenit - do they make them out of the bottoms of old vodka bottles?). Anyway, I had no problems when I reverted to using spot metering nor did I have any problems with either setting when using a VS 35-70. Wilson
 
> If you were using an exposure meter, what would you dial in for Velvia> - ISO40 or ISO50? And how would you then translate that into your> camera? Is it therefore possible to calibrate your camera against a> handheld meter (assuming that was correct!!)?

Well , I only really hinted at it before but I use both speeds!! If its miserable and overcast I'll leave it on 50 typically , but when the sun here beats down I'll shoot on 40 otherwise its just too contrasty most times . With my 139 and 167 I will just adjust the film speed dial and slider accordingly - cant remember how to change it on my RTS 3 just at this second , but thats probably because I tend to stick to Provia F these days . I'd be interested to know if some people think it necessary to do something similar to the new Velvia 100 - I believe its quite a different beast to the older emulsion though , so maybe not..... Steve
 
>>>>>>>>>remember him implying that "they" had altered the exposure and that > his explanation was that it was to give a "more saturated" look. Popular Photo, in testing various Contax bodies, including the RTSIII, said the same.

The alteration probably was made in the calibration or adjustment. It seems more likely they decided, "let's alter the exposure". Reminds me of an anecdote involving Marty Forscher, repairman. A customer brought a camera w/meter to be calibrated. Said all exposures were off (overexposed?-I forget which). So MF adjusted the meter, customer returns and says they are all now underexposed. MF adjusts it again, in between the values, and customer returns, "some are overexposed and some are underexposed". The moral of the story is to know how your meter works and use it to achieve the desired result. You will always have variables even if the meters are calibrated exactly, as the differing patterns of measurement, spot, small field, center weighed, will vary somewhat. We don't usually photograph things that are even in lighting and texture. And that's not even talking about the so-called "matrix" metering. How many times have you done a spot or incident meter, or knew the sunny f/16 rule (f/16 with the reciprocal of the film speed for the shutter speed, e.g. f/16, ISO 100, 1/125 sec). But you were distracted by a "different" measurement value that your camera/meter on automatic suggested?
 
Wilson

I invariably use the RX on centre-weighted metering, and about 75% of the time when I'm outdoors I'll use the 25mm so there is of course a real danger of underexposure when you've got so much sky - I tend to take an averaged-out reading from the ground when conditions look difficult.

Don't quite understand what you're saying about the Med though, wouldn't lots of specular reflection (there I'm showing off now) from water tend to make you underexpose, rather than overexpose?

I'm sure that I agree with what nearly everyone has said here - it's all very well knowing the science and the technicalities (and you do need a certain understanding of this) but ultimately you need to find a working method which means that you take good pictures (and understand why bad ones occur and what to do about them next time).

And that's the main reason for asking the question really. I have a working method for Provia 100F (which involves downrating it, or overexposing it if you like). This working method went out of the window with my first roll of Velvia 100F so I need to reappraise and learn why, all of a sudden, I seemed to be making not so good pictures.

Now I know that the best answer is for me to throw loads of reels of Velvia at my RX (metaphorically) and I haven't had the time to do that yet.

In the meantime, has anyone else found Velvia 100F to be faster than Provia?

Ta
John
 
Bob,

> The answer I got from Kyocera was even more
> curious!!

I agree, that's why I said it was puzzling.

> I now wonder if the "alteration" was simply a
> consequence of using (for ex&le) different
> meter sensors or different electronics in the
> "newer" cameras, compared with "older" cameras,
> and maybe not a case of "let's alter the
> exposure". I doubt that we will ever know for
> sure.

Yea, sounds like X-files to me ;) We will probably never know.

> I would welcome other's opinions if they have
> owned both older and newer Contax models

I would be also curious to hear about that, especially since I'm contemplating buying used RX or RTS III.


Mr Wilson Laidlaw,
> probably best to ignore that one since it was a
> Zenit - do they make them out of the bottoms of
> old vodka bottles

AFAIK they're using trophy equipment from WWII time that they hauled from Germany. It could be that they're recycling vodka bottle glass though ;)

Mike.
 
John Walton,

> In the meantime, has anyone else found Velvia
> 100F to be faster than Provia?

I guess I will find out in about a week, since I just got few rolls of Velvia 100F recently. Although, I personally shoot Provia on its rated speed (ISO 100). I use Aria primarily, but also used N1. For the most part, I like the results at ISO100, although I must say, when I shoot slide I almost always use spot meter.

Mike.
 
Back
Top