Filters for ZWO1600M Pro

[teoria_del_big_bang]

A couple of questions regarding ideal filters for DSO's when using a ZWO 1600M Pro camera.

LRGB

According to ZWO you are better off using their filters designed for this camera a opposed to other well know and trusted brands such as Baader. Does anybody have any evidence of this? 

Most LRGB filters have some form of IR block but if using in areas where there is some form of light pollution is it good practice to also have a good LP filter in line somewhere such as the IDAS P2 ?  If so where is best to place it, just after the flattener,  After writing this I realised this is probably not the best place as it will affect the back focus of the flattener and without changing my spacers, taking into account for the way the diffraction withing the filter affects the light path, I will not have correct back focus. SO I suspect it is best to put the filter in front of the flattener.

There is a Baader LRGBC filter set. When would you use the clear filter? 

Steve

Edited July 21, 2019 by teoria_del_big_bang

[Starwiz]

I've only recently started with an ASI1600mm Pro myself, using the ZWO filters.  It's recommended to place them as close as possible to the sensor to help reduce vignetting.  I don't use a field flattener, so can't comment on this.  I know ZWO have made some improvements recently, to reduce light leakage at the edges of the filters if I remember rightly.

John

[teoria_del_big_bang]

Hi John,

I too am very new to the ASI1600. My LRGB filters are as close to sensor as possible, but they are not ZWO filters and the couple of times I have had chance to use them this summer I have had some vignetting using 1.25" filters (Astronomik I think they are) so wondered if the ZWO ones would be better, or maybe go to 36 mm or 2" filters but this could get expensive with NB as well.

But I have read that some people also add a LP filter in addition to the LRGB which obviously then has to go elsewhere than the filter wheel. So my thoughts are at present is to fit it in front of the flattener to avoid affecting the back focus of the flattener.

Steve

[david_taurus83]

What flattener do you have? Some allow threading of 2 inch filters on the front end.

[Starwiz]

12 minutes ago, teoria_del_big_bang said:

Hi John,

I too am very new to the ASI1600. My LRGB filters are as close to sensor as possible, but they are not ZWO filters and the couple of times I have had chance to use them this summer I have had some vignetting using 1.25" filters (Astronomik I think they are) so wondered if the ZWO ones would be better, or maybe go to 36 mm or 2" filters but this could get expensive with NB as well.

But I have read that some people also add a LP filter in addition to the LRGB which obviously then has to go elsewhere than the filter wheel. So my thoughts are at present is to fit it in front of the flattener to avoid affecting the back focus of the flattener.

Steve

As I understand it, you shouldn't need a light pollution filter for the RGB component, as the filters deliberately exclude the band of sodium light between green and red.  Luminance may benefit from a LP filter, but I've no experience on this.  I'm using the 31mm unmounted filters and also have the Ha, OIII, SII for narrowband.

John

 

[teoria_del_big_bang]

13 minutes ago, david_taurus83 said:

What flattener do you have? Some allow threading of 2 inch filters on the front end.

Its the WO Flat73 (not the newer 73A with adjustable spacing). I have actually just found this thread started by @fwm891 which shows the filter on the front end of my flattener. So that answers one of my questions. However, do I leave this filter in if using NB fiters. I am guessing although not required it will not have a massive effect either way.

 

[david_taurus83]

I leave my D2 in for all filters.

[teoria_del_big_bang]

Okay so another novice question.

If I have a LP filter permanently in the imaging train, specifically the IDAS P2, when taking luminance does it matter if I use a proper luminance filter or just the clear filter.

A clear filter would then just rely on the LP filter to block IR but keep everything more in focus and retain the back focus from the flattener.

Would using the L filter as well as the LP filter block more light or not?

Steve

[Adam J]

On 21/07/2019 at 18:53, teoria_del_big_bang said:

A couple of questions regarding ideal filters for DSO's when using a ZWO 1600M Pro camera.

LRGB

According to ZWO you are better off using their filters designed for this camera a opposed to other well know and trusted brands such as Baader. Does anybody have any evidence of this? 

Most LRGB filters have some form of IR block but if using in areas where there is some form of light pollution is it good practice to also have a good LP filter in line somewhere such as the IDAS P2 ?  If so where is best to place it, just after the flattener,  After writing this I realised this is probably not the best place as it will affect the back focus of the flattener and without changing my spacers, taking into account for the way the diffraction withing the filter affects the light path, I will not have correct back focus. SO I suspect it is best to put the filter in front of the flattener.

There is a Baader LRGBC filter set. When would you use the clear filter? 

Steve

I use Baader with mine and love the colour balance that I get from them, I tend to think this idea that they are matched to the sensor is a bit of cleaver marketing. Baader are well known in the hobby as a producer of fine quality filters, on the other hand ZWO have had quality issues with some of their filter products although they have made improvements. 

[teoria_del_big_bang]

1 minute ago, Adam J said:

I use Baader with mine and love the colour balance that I get from them, I tend to think this idea that they are matched to the sensor is a bit of cleaver marketing. Baader are well known in the hobby as a producer of fine quality filters, on the other hand ZWO have had quality issues with some of their filter products although they have made improvements. 

Thanks for that, I had sort of come to the decision to go with Baader. My next issue is whether to go the 36 mm unmounted or 2" mounted. I know with this ccd I should be okay with 1 1/4" but to ensure vignetting is definitely kept to a minimum wanted to go a bit bigger.

36 mm would be fine and more over lets me use a 7 position wheel so that I can have all filters permanently mounted.

2" maybe overkill but means I have some decent filters that would last me and would cater for any future needs(I doubt I will ever justify the cost of Astrodons), but that means using a 5 position wheel and changing between LRGB and NB but this is a minor thing and not really an issue just need to decide if I would be better off with 2" or whether 36mm would suffice.

Steve

[Adam J]

7 minutes ago, teoria_del_big_bang said:

Thanks for that, I had sort of come to the decision to go with Baader. My next issue is whether to go the 36 mm unmounted or 2" mounted. I know with this ccd I should be okay with 1 1/4" but to ensure vignetting is definitely kept to a minimum wanted to go a bit bigger.

36 mm would be fine and more over lets me use a 7 position wheel so that I can have all filters permanently mounted.

2" maybe overkill but means I have some decent filters that would last me and would cater for any future needs(I doubt I will ever justify the cost of Astrodons), but that means using a 5 position wheel and changing between LRGB and NB but this is a minor thing and not really an issue just need to decide if I would be better off with 2" or whether 36mm would suffice.

Steve

I cant really help you with that as I am using 1.25 inch without any vignetting at F5 so unless your going sub F4 or think you will get a bigger sensor in the future I really would not advise you to go any bigger, all its going to do is cost you money for no benefit and in fact the biggest result will be that you wont get as many slots in your filter wheel.  

I have performed the calculation myself, there really is no vignetting on 1.25 inch filters. Certainly not on any of the scopes you are listing in your signature block.

I use Astrodon for my narrow band in addition to the Baader LRGB filters. No chance of affording those in 36mm or 2 inch.   

Adam

[upahill]

46 minutes ago, teoria_del_big_bang said:

Thanks for that, I had sort of come to the decision to go with Baader. My next issue is whether to go the 36 mm unmounted or 2" mounted. I know with this ccd I should be okay with 1 1/4" but to ensure vignetting is definitely kept to a minimum wanted to go a bit bigger.

36 mm would be fine and more over lets me use a 7 position wheel so that I can have all filters permanently mounted.

2" maybe overkill but means I have some decent filters that would last me and would cater for any future needs(I doubt I will ever justify the cost of Astrodons), but that means using a 5 position wheel and changing between LRGB and NB but this is a minor thing and not really an issue just need to decide if I would be better off with 2" or whether 36mm would suffice.

Steve

I am building my proper imaging set up slowly and had to make this decision too - went for the 36mm as a middle ground. It was ultimately influenced by a deal on a set of HA/SII/OIII filters at FLO but I liked the idea I could have 3NB+LRGB in one wheel with the ZWO 7x36.

I didn't buy into the whole "matched to the sensor" marketing, maybe its true, no idea - but have used Baader before and been happy so went with their filters.

2" might have given me better future proofing but the cost jumps significantly and so does the wheel problem.

If I ever get the camera ill be able to test them

 

[teoria_del_big_bang]

1 minute ago, Adam J said:

I have performed the calculation myself, there really is no vignetting on 1.25 inch filters. Certainly not on any of the scopes you are listing in your signature block.

I use Astrodon for my narrow band in addition to the Baader LRGB filters. No chance of affording those in 36mm or 2 inch.   

Adam

I agree 1.25" or 31mm would be fine for my current setup it. The cost difference does not worry me too much as it is not massive (about £475 for 1.25", £615 for 36 mm unmounted, £700 for 2") so to future proof them I would pay the extra.

But yes you do make a good point about whether I will ever get a bigger sensor and as I am shortly to retire to splash out probably £2000+ in the future does seem unlikely.

I guess especially for NB the Astrodons must be worth it as they are so much more expensive people would only do so if that were true. I guess for now I would have to either forget NB for a year or so or use my current astronomik ones and save or just decide my pockets are not that deep and to get the Baader ones.

I have read also that the unmounted ones can cause issues with reflections if not sealed around the edges - any thoughts on this.

Steve

[teoria_del_big_bang]

@upahill Thanks for the reply, I just had to laugh when I saw caffeine in your equipment but agree how important this is on a night. I assume as it is listed after the Baader items it must be filter coffee you are using 🤣

Steve

[upahill]

3 minutes ago, teoria_del_big_bang said:

I have read also that the unmounted ones can cause issues with reflections if not sealed around the edges - any thoughts on this.

Steve

Not something I have read, hopefully it wont be a problem, or will be easily solveable.

I looked at the Astrodons but couldn't justify it for my first foray into NB. Ended up with a set of ex-display Baader 36mm unmounted for £250 - will upgrade them if I ever find the need to. I just didnt want to have to come down to a 5 position zwo wheel.

Still need to source the LRGB, but will wait for the right deal.

 

[upahill]

Just now, teoria_del_big_bang said:

@upahill Thanks for the reply, I just had to laugh when I saw caffeine in your equipment but agree how important this is on a night. I assume as it is listed after the Baader items it must be filter coffee you are using 🤣

Steve

We run an espresso bar, so its locally roasted brazillian beans freshly ground espresso 😉. It would be filter if I wasn't buying wholesale!

But yes I would be nothing without my coffee!

[teoria_del_big_bang]

5 minutes ago, upahill said:

Not something I have read, hopefully it wont be a problem, or will be easily solveable.

will see if I can find it again and let you know. It was easily solved by sealing the edges with either tape or carefully applying paint (only to edges mind obviously). This may be unfounded or I may have misread something as I was not really considering unmounted at the time so did not look too closely.

Steve

Edited July 23, 2019 by teoria_del_big_bang

[Adam J]

 

59 minutes ago, teoria_del_big_bang said:

I agree 1.25" or 31mm would be fine for my current setup it. The cost difference does not worry me too much as it is not massive (about £475 for 1.25", £615 for 36 mm unmounted, £700 for 2") so to future proof them I would pay the extra.

But yes you do make a good point about whether I will ever get a bigger sensor and as I am shortly to retire to splash out probably £2000+ in the future does seem unlikely.

I guess especially for NB the Astrodons must be worth it as they are so much more expensive people would only do so if that were true. I guess for now I would have to either forget NB for a year or so or use my current astronomik ones and save or just decide my pockets are not that deep and to get the Baader ones.

I have read also that the unmounted ones can cause issues with reflections if not sealed around the edges - any thoughts on this.

Steve

I have heard of that problem with ZWO 36mm and 31mm unmounted filters without blocked edges. I have not heard about any issues with Baader 36mm filters. 

Personally if it was me I would get Ha and OIII first then get the LRGB later as opposed to the other way around as if you want to image emmission nebula you will get vastly better results in narrow band. Of course if you want to image galaxies or M45 then go LRGB. 

Try to work with filters that are close to the same thickness as it avoids issues, ie. using Astronomik LRGB (1mm) and Astrodon Narrow-band (3mm) might lead so back focus issues. 

Adam 

[david_taurus83]

I've got the 36mm Baaders and it allows me a bit of headroom to offset the camera further back from the filterwheel (I've fitted a camera rotator adapter) I've I was to buy filters again, I'd look at the new ultra narrowband ser from baader. Especially the Oiii as the 8.5 is Halo City!

[Starwiz]

1 hour ago, teoria_del_big_bang said:

I just had to laugh when I saw caffeine in your equipment

I'll have to add beer to mine then. 🍺

John

[teoria_del_big_bang]

18 hours ago, david_taurus83 said:

I've got the 36mm Baaders and it allows me a bit of headroom to offset the camera further back from the filterwheel (I've fitted a camera rotator adapter) I've I was to buy filters again, I'd look at the new ultra narrowband ser from baader. Especially the Oiii as the 8.5 is Halo City!

I think I am settled on getting 36 mm filters. For the same reasons as you have mentioned. Also the mention of the Baader Ultra NB filters mad me think again. They are a fair bit more expensive than the original Baaders, still cheaper than the astrodons but may be a good compromise, especially as you are not the first to mention the halo issue.

So my issues are solved eh, not quite. Next issue is getting hold of some. They seem to be pretty short on supply at the moment, especially in anythng other than 1.25". FLO had an estimate of 40 to 60 days delivery but an email to them has revealed they really cannot give an eta at all (or rather Baader cannot).

God if somebody had told me a few years ago before I got into this that I would be willing to pay well in exsess of £200 for a bit of coloured glass not much bigger than a coin I think I would have choked.  But these bits of glass can make all the difference.

Steve

Edited July 24, 2019 by teoria_del_big_bang

[MattJenko]

If you get the filter wheel oriented so the filter surface is closest to the camera side and attach the ASI1600 right up to the filter wheel, then 1.25" filters are absolutely fine. I have used Baader LRGB + NB filters, a Chroma 3nm Ha 1.25 filters and ZWO's own and see precious little vignetting from any of them. The ZWO filter wheel has the filter surface pretty close to the thread so works well, the SX wheel I have is a little further away, so I use the ZWO one exclusively with the ASI1600 now. And to be honest, even if I had noticeable vignetting, it normally processes out really easily. For a £50 difference in the current LRGBHa bundles on FLO (or £100 for the full NB set), its not a major issue either way so you won't be making a mistake choosing one over the other, unless you want to buy 3nm filters

[teoria_del_big_bang]

I decided to go for the Baader Ultra NB filters and managed to get Ha and OIII from Ian King but cant seem to get a SII for love nor money at present so will have to wait for that one.

I have gone for the 36 mm and ordered the LRGB set from FLO.

So hopefully may have a full set before the longer clearer nights come (if they come). 🙂

Thanks to all for the advice and help.

Steve