Stacking UV/Ir cut filters on the 2600MC-Pro

jimme100

Hello All,

I am hoping I might get some input from @w7ay 🙂

My question: Should I use a better UV/IR cut filter (Baader cmos optimized UV/IR cut filter)together with my built in zwo UV/IR cut filter on the 2600MC or should I replace the ZWO filter with the AR window and use the Baader with better cutoffs in the UV and IR. I really dont want to do the AR replace if i dont have to but I would surmise that having more glass and inferior glass in the built in filter used in combination with a high quality filter would not be what I would want to do. will i be fine with the 2 filters?

I have been seeing slightly bloated/softness/slight blurriness in my stars and halos especially in the blue with the built in ZWO UV/IR cut on the 2600MC. Someone at starfront said they saw an improvment after replacing the built in filter with the AR window and using a high quality filter. I see that @w7ay has done some analysis and that the ZWO built in filter doesnt perform well in the UV or IR range.

I am sending an Ultracat 108 to starfront in the next few months. I already have an older Gen1 spacecat 51 rig there. I am looking to get the ultracat 108 setup as maximized as possible. Another consideration is that the 108 may be better corrected in the blue than the older spacecat 51 so maybe the bloating may be less of an issue? I really need some advice here.

I see some forums just saying to leave the built in UV/IR filter and to use a better UV/IR cut filter (Baader cmos optimized UV/IR cut filter) together with no impact to image quality, although I dont know the level of imaging expertise for those suggesting to do this.

I really dont know what to do here. Should i just use both UV/IR cut filters for a slightly better cutoff? should i replace the built in filter with an AR filter?

Will using both filters be ok and not?

Any advice would be appreciated!

Regards,

Jim-

retman

jimme100 chen passed away a few months ago. I have 2 2600mc pros and use an additional uvir filter with the zwo filter holder. I use an optolong filter and notice no negative effects.

Tech@ZWO

Adding another filter glass will not completely filter out the extra light.In reality, our current IR Cut filter achieves approximately 92% transmittance for light wavelengths between 400-700nm. It cannot guarantee full transmission, as partial reflection may occur, potentially causing halo artifacts. Even if you switch to alternative filters, residual reflections will persist—though some may offer marginal image quality improvements.

probro1154

I have the Optolong 2" UV/IR filter, but haven't noticed any real difference with or without it on my 2600MC-Duo. I still use it because it's parfocal with the L-enhance filter and I don't have to refocus when I change filters.