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IR filter -should it always be attached?


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Hello, the IR filter that came with a 1482MC…..should I always have it connected to the camera or …..if I use the supplied CH4 filter, do I swap that with the IR or use them both at the same time?  So my question is really do I use the IR with any other filters or should I take the IR filter off if using another filter? 


There is a bewildering amount of filter info but I am at the new stage where most of the info might as well be written in Swahili! I’ll get there in the end but my brain is full at the moment. 
 

thanks

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If the charts of FLO’s site are to be believed, the ZWO UV/IR cut filter has a band pass between 400-700nm (chart 1) and the CH4 band pass is 20nm centred around 890nm (chart 2) so if you use them together you’ll draw a blank because the band pass of the first filter will be blocked by the second filter…so I’d try them separately.

Just adding to Vlaiv’s point- in general you could use the UV/IR cut with other filters e.g R G or B or OIII or Ha because the passbands for those fall within the passband of the UV/IR cut, but you may not need to because these filters will also often (but not always) cut the UV and IR regions. However, if you do stack filters, the focus will probably be shifted compared to using single filters- so in general I’d suggest using them singly.

FC69254D-04D4-4353-884D-3BF7E847F3D3.jpeg

29934855-FCC0-4F85-8B80-37E2BC83BC15.jpeg

Edited by catburglar
Added comments about stacking filters
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1 minute ago, catburglar said:

If the charts of FLO’s site are to be believed, the ZWO UV/IR cut filter has a band pass between 400-700nm (chart 1) and the CH4 band pass is 20nm centred around 890nm (chart 2) so if you use them together you’ll draw a blank because the band pass of the first filter will be blocked by the second filter…so I’d try them separately.

Yes, that is true, however, from OP - it is not clear if it is IR pass or UV/IR cut filter that is mentioned.

IR pass filter can be stacked with CH4 - although it won't bring in any benefit to do so - but rather somewhat reduced total transmission.

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4 minutes ago, vlaiv said:

Yes, that is true, however, from OP - it is not clear if it is IR pass or UV/IR cut filter that is mentioned.

IR pass filter can be stacked with CH4 - although it won't bring in any benefit to do so - but rather somewhat reduced total transmission.

True- I assumed the OP was referring to the package that’s offered at FLO with camera, uv/ir cut and CH4 filters…but you are correct it’s not clear

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5 minutes ago, catburglar said:

True- I assumed the OP was referring to the package that’s offered at FLO with camera, uv/ir cut and CH4 filters…but you are correct it’s not clear

I was not aware of the bundle, so yes, it is most likely the case that it is IR/UV cut filter.

In either case - your advice is very sound. One should look at respective QE graphs of transmission and multiply them if attempting to stack filters.

Sometimes it can be beneficial but in most cases - it simply lowers efficiency of the setup - or even, like you pointed out, causes complete blockage of light.

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52 minutes ago, catburglar said:

If the charts of FLO’s site are to be believed, the ZWO UV/IR cut filter has a band pass between 400-700nm (chart 1) and the CH4 band pass is 20nm centred around 890nm (chart 2) so if you use them together you’ll draw a blank because the band pass of the first filter will be blocked by the second filter…so I’d try them separately.

Just adding to Vlaiv’s point- in general you could use the UV/IR cut with other filters e.g R G or B or OIII or Ha because the passbands for those fall within the passband of the UV/IR cut, but you may not need to because these filters will also often (but not always) cut the UV and IR regions. However, if you do stack filters, the focus will probably be shifted compared to using single filters- so in general I’d suggest using them singly.

FC69254D-04D4-4353-884D-3BF7E847F3D3.jpeg

29934855-FCC0-4F85-8B80-37E2BC83BC15.jpeg

Thanks that makes sense. I think. I appreciate the explanation.  

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