Does anyone have information they can share on the following Gossen Luna Pro Attachments?
I have a Gossen Luna-Pro F and would be interested in getting the measuring probe if it could be used as a film plane meter on a Sinar 4x5 f. I would also be interested in the spot (Gossen more correctly refers to it as a variable angle) attachment.
Your views are, as always, appreciated.
I have the analogous attachments for my Minolta meter.
Groundglass readings tend to work best in the studio or at least indoors, where you can more easily shield the back from stray light. Outdoors where you're dealing with wind and the brightness of sunlight, it's easier just to take a spot reading and make the necessary calculations.
I often use a 5-degree finder and can usually manage to get the information I need from it, but there are times when a real 1-degree spot meter would be more useful.
I already had my meter, and rather than buying a spot meter, I economized and bought the attachment for my Minolta. I've just started using it, and most of the time it's fine, works like a charm. I can remember there being only one situation where a one degree would have been better.
I also have Minolta experience but it applies to the Gossen also.
A couple of years ago I bought a used Minolta that came with 5 degree attachment and also the booster probe. Like David says the probe can be used indoors on groundglass but is near impossible in bright room light. I have never found it to be really useful and I just play with it. I certainly wouldn't pay for another one but I am thinking about making a densitometer with it.
The 5 degree was OK, but after I got a 1 degree meter I will never go back. I now have a Sekonic with 4-1 degree zoom spot and can only remember using the 4 degree setting once.
I also disliked having to carry around and remove and replace attachments to go from spot to incident and back. IMVHO you should get an all in one like the Sekonic, or even better would be to add a dedicated spotmeter to your Gossen.