Best way to construct a filter

[motorhead9999]

Yep, we all do get intense sometimes. But that is only because we love this stuff and really enjoy talking about it.

 

Mike, I am *really* looking forward to seeing photos from your new full spectrum S1R. That is my next conversion if ever I can get some time. I've been sidetracked for the last 6 months by getting our new house set up. That has included far too many distractions such as roof repairs, gutters and drainage installation, major landscape and garden renewal and endless unpacking.

 

Will do. Can I ask why specifically you're interested in the S1R? I'm curious if your reasons end up the same as mine.

[ulf]

Reed -

 

Sorry, that I jumped to conclusions.

I must have read in some hidden marketing quarrel, that might not have be there, in your debate with Steve, as you in a way are competitors, both selling filters for UV-photography.

 

All your fact statements are correct, even if not all of them are very important in most situations and can often be ignored or compensated for.

 

I was triggered by that you, at least for me, seamed to indicate that the pure Baader U-style is the only important and valid as it is the most used by so many.

If that is the goal for a filter to give such type of images, indeed there are many ready-made cheaper alternatives that are glued.

 

I am a bit fed up seeing just that type of images.

Especially as there is much more to discover with other filter combinations, mostly lacking pre glued alternatives.

[Cadmium]

It is impractical to glue every stack, and also not at all versatile, no experimentation, no discovery.

My tests with the #729 + KG3 2mm, separate filters and glued seemed to have the same results.

Indeed, a glued stack of those two filters with clear cladding on the other side of the #729 is convenient, but only if you want to use the KG3 for that use only.

The most important part to learn first about the #729 + KG3 2mm stack is how to white balance it, I won't go into all that again here, but you will not see any great diference

between those two filters screwed together and those two filters glued. If you do glue them, then first learn to white balance the screwed together stack first,

because if you're not happy with the screwed together results, your going to be just as disappointed once you glue them, maybe more because you can't use the KG3 for anything else now.

So my advice, if it were me, and I only had one KG3 2mm filter, I would not dedicate it to only one use, I would keep it as a separate filter so I could use it for many varied stacks.

Perhaps my versatility advice has no place in this topic, however my polyester glue smearing advice would be good to take note of.

Once again, my advice if you only have enough money to buy one KG3 2mm, then don't glue it to anything, keep it separate so you can experiment using it in other stacks.

Gluing might be fun though! So there is that... Try not to inhale the stuff, read the Material Safety Data Sheet for the glue you use first.

[dabateman]

Just as the innocent bystander who started this, as of this time, I was really just trying to get a handle on getting started. I'm still testing out the aerochrome examples I've found online out, so once I settle that and am happy with the results, then maybe I'll start considering cementing. Right now I just need to get an image that (roughly) works! I have rolls of the 729, and I have some Roscoe 8000 dichroic glass on order. Once that comes in (hopefully end of this week or monday), I can do a full test. I (hopefully) should also have my new full spectrum S1R delivered by then too.

 

One other question: Is there any sort of gel or polyester filter that does the same as the KGS3 or Roscoe 8000 IR? I've used them for my fisheye and ultra-wide lenses in the past, but haven't tried any sort of IR cutting material.

 

Yes its a fun place here.

 

Roscoe 8000 I will assume to be significantly different than KG3 and might not work for you. But since you will have it you should test it. I got some GRB3, the Chinese equivalent to KG3 and it is really not even close. After ordering genuine 15 mm disc of KG3, I see they are significantly different. The GRB3 is harder to white balance and is more orange than the reds that the KG3 provide.

 

Sadly there is no polyester gel, at least in the whole free Lee filter pack that will cut like KG3. I have tested them all. Also you can't use a weak IR cutting camera like an Olympus to take the place of KG3. That too did not work. It seems all of the Lee polyester filters will leak various amounts into the IR.

This is bad for the Red filter, but good to get really cheap various IR filters by just stacking Lee ones. Stacks like Lee 746 with 120 or 707 are fun to play with.

 

For the Panasonic 7-14mm lens, which I have modified to have back gel filter holder, you can get away with just the Lee 729 filter if you have already a good custom white balance and the sunlight is just right.

 

The only other filter that I have that has the red look is a 1.25 inch Parks 38A filter. Using my custom UVB white balance setting (Kelvin over 14000), it gives excellent reds and I use it reverse mounted in lenses.