Quark and filters as ERFs

[skybadger]

Hi 

I'm using a quark chrome H-alpha filter on a skywatcher ST80 and I want to put a pre-filter in front to dump some of the heat. To this end I put a Baader 2" IR cut filter in the train and more or less lost the surface detail. 

Can anyone recommend a filter for this job and maybe explain why the filter had the effect it did ?

Also, my quark seems to be on-band with the knob turned to 1 o' clock when previously it was at about 6. All I did was store it indoors over the winter. Has this happened to anybody else ? Ambient is about 15 to 20 degrees in the obbo.

In the meantime I replaced my ST80 with a Stellarvue ED80 at f/7.     On the basis that maybe the f ratio was too steep for the etalon to give good performance . While I get more contrast off the disk, I am not seeing an improvement on disk. So then I followed a suggestion to use a Baader HA 35nm filter as a pre-filter to reduce the heat loading. That actually has the same effect of removing contrast (and hence detail) too. Back to where I started.

Is the only answer to this a full aperture ERF ? While an 80 mm is at the top recommended limit for use without a pre-filter, it would be good to find one that doesn't ruin the view. 

Finally how clear is the surface detail in your quark ? In mine it's low contrast and requires tapping the tube  to see , using a 20mm eyepiece. Any pointers to optimise this ?

Cheers

Mike

[Merlin66]

Hmmmm

Not sure where the "reduction in contrast" is coming from.

For an 80mm the UV-IR I would have thought would be more than sufficient...

The Baader 35nm Ha CCD - I've used it extensively as an ERF - it has exactly the same construction as the D-ERF filters. Adding an external D-ERF will give you the same result.

I have heard that using an ERF can cause the Quark to be "cooled" and tune differently - I don't have one so can't confirm.....

 

[skybadger]

Hi Michael.

I thought that myself, but the broad band photospheric limb hedgerow stuff that is always there just disappeared too. That is normally there over the wide  range of tuning.

Also , I might run out of reduction to tune it to , if anti-clockwise is to the blue and lower regulation temperature.

Any other quark owners ?

[Davey-T]

Doesn't sound right, I use the Baader 35nm on mine and it doesn't affect the views.

Unfortunately there is a lot of variability in Quarks, some are superb and others merely average, I had mine replaced after the tuning failed but the replacement is not as good as the original.

I would seriously consider returning it to Daystar either direct or through the dealer it came from originally, it will still be under guarantee.

Dave

[Lowjiber]

I have a Quark Chrome that I use for imaging on an ST-80 (f/5) and a SW ProED 100.

While Daystar says an UV/IR cut isn't required on an 80 mm, I run the Baader version (2") on the front of my diagonal anyway and, obviously on the 100mm SW.

In my opinion the Quark is not all that great of a visual device, when compared to a Lunt for example.  That said, I don't lose anything imaging with the UV/IR cut filter on the ST-80.  As others mentioned, there is quite a bit of variance between identical Quarks.  I do find that I needed to back off (from +4 to +3) when imaging the surfaces with the filter installed.

[Davenn]

On ‎18‎/‎10‎/‎2017 at 12:05, Lowjiber said:

I have a Quark Chrome that I use for imaging on an ST-80 (f/5) and a SW ProED 100.

While Daystar says an UV/IR cut isn't required on an 80 mm, I run the Baader version (2") on the front of my diagonal anyway and, obviously on the 100mm SW.

I took delivery of a Camera Quark Chromospheric filter a couple of days ago ( to suit my Canon EOS)

I have been experimenting with it on my 100-400mm L lens with a 2 x teleconverter. Noting that the lens has an aperture of just on 80mm. I thought it prudent to put my Baader film filter over the front

for an initial trial.  Well that didn't work, as the sun was not visible. Taking it off gave a good view of the sun ( after to 10min or so warm up time of the filter heater, of course   )

I still have some concern about aiming my expensive L lens at the sun without a pre-filter, but I appear to have no other choice.  Daystar seem to indicate that it should be OK 

The only consolation, is that I'm not aiming at the sun for long periods ( hours on end)

 

Dave

 

 

[Davey-T]

2 hours ago, Davenn said:

I took delivery of a Camera Quark Chromospheric filter a couple of days ago ( to suit my Canon EOS)

I have been experimenting with it on my 100-400mm L lens with a 2 x teleconverter. Noting that the lens has an aperture of just on 80mm. I thought it prudent to put my Baader film filter over the front

for an initial trial.  Well that didn't work, as the sun was not visible. Taking it off gave a good view of the sun ( after to 10min or so warm up time of the filter heater, of course   )

I still have some concern about aiming my expensive L lens at the sun without a pre-filter, but I appear to have no other choice.  Daystar seem to indicate that it should be OK 

The only consolation, is that I'm not aiming at the sun for long periods ( hours on end)

 

Dave

 

 

As you say Daystar say it will be fine so I doubt if they will be willing to contemplate any compensation if some bit of plastic inside a camera lens melts.

I'd be inclined to by a cheap refractor and try to use that instead not sure how it would attach though, I've used a SW ST80 with my Quark.

Dave

[AdeKing]

I'm not sure that the Baader solar film is suitable as an ERF for a quark as it's designed for white light observation, not Ha and I'm pretty sure that it will block too much light for the Quark, which sounds like that's what happened if the disc wasn't visible.

Just been on the Daystar website to look at the Quark Camera and saw the following notice. "All Daystar Hydrogen a filter assemblies need to be used in conjunction with a lens cover and Energy Rejection Filter" at the bottom of the left hand menu bar under the product delivery timescales which seems to contradict the 80mm statement in the Quark flier.

I've only started solar observing this year and am no expert but I think I'd be with @Davey-T in that I'd rather get a cheap refractor than try to use an expensive Canon L lens as I'd have thought that the lens would contain a myriad of plastic parts that could be damaged by the unfiltered sun if there is no ERF on the front of the lens.

[Davenn]

19 hours ago, Davey-T said:

I'd be inclined to by a cheap refractor and try to use that instead not sure how it would attach though, I've used a SW ST80 with my Quark.

Dave

that's the easy part .... just a T ring adaptor to the 1.25" or 2" eyepiece needs of the telescope

I haven't actually taken pix through it yet with a camera.   just been using it with an eyepiece for visual observing

 

19 hours ago, AdeKing said:

Just been on the Daystar website to look at the Quark Camera and saw the following notice. "All Daystar Hydrogen a filter assemblies need to be used in conjunction with a lens cover and Energy Rejection Filter" at the bottom of the left hand menu bar under the product delivery timescales which seems to contradict the 80mm statement in the Quark flier.

 

 and even on another place on the same page 

 

The user hand book, and I use that term loosely, that came with it also states using a filter for 80mm aperture and over and zero comments about coloured glass or other filters over the front of the lens

19 hours ago, AdeKing said:

I'm not sure that the Baader solar film is suitable as an ERF for a quark as it's designed for white light observation, not Ha and I'm pretty sure that it will block too much light for the Quark, which sounds like that's what happened if the disc wasn't visible.

I am sure... hahaha .... take my word for it,  it doesn't work ... zero visibility

 

 

Dave