Ian McCallum

I inherited a twist lock 2" adapter similar to this, when I bought a second hand telescope last year.  It seems to have 48mm filter thread inside, for 2" filters obviously.  My question is, can I get a 48mm to 42mm adapter ring to fit this, so that I can use it my SW Skyliner 200P focuser tube, I think that has a 42mm T adapter or something similar on it? That way, I can do away with the focuser tube with the thumbscrews on it.

3 hours ago, StuartJPP said:

You won't be loving it when it is unscheduled and part of daily life, just ask any South African.

Isn't that due to copper thefts?🤔

20 hours ago, cajen2 said:

Good buy, Ian. You must tell us how you get on with it.

A quick visual only report, as I had mount problems last night.  Without the filter, CA was obvious around the Jovian disk.  With the filter, it was nearly as good as the view with my 8" Dob.

@Stu A mount upgrade is out of the question, as I've already thrown enough money at this.🙄 If I don't manage to get half decent results with what I have, then at some point I will go back to purely visual observing.  I'll sell the cameras, etc. and try to recoup some of the cost...

1 hour ago, cajen2 said:

Good buy, Ian. You must tell us how you get on with it.

It might be sometime away, due to the long range weather forecast!🙄

From Auntie @FLO... 

3 hours ago, Franklin said:

EQ5 is rated at 9kg.

Hence my question.😉

11 hours ago, Stu said:

Given that planetary imaging benefits from aperture to maximise the resolution, I reckon sticking the 200p on an EQ platform would be well worth trying. They are pretty simple to set up, and will track for 45 mins or so, plenty long enough for imaging captures which would only be a few mins.

Would my SW Skyliner 200P not be too much weight for the EQ5 GOTO mount?  The OTA alone weight in at 11kg.

Wow!😲

6 minutes ago, Zermelo said:

Last night I was comparing (not for the first time) the Baader semi-APO with an unfiltered view, on Jupiter with my Skymax 127.

I bought the filter mainly for fringe-killing on my achromat, bbut with a possible secondary use as a planetary filter with any scope (it uses the neodymium substrate).

I've tried coloured filters on planets but didn't like them and found they removed detail, including the Wratten yellow. The semi-APO does give a yellow cast, but not too bad, and after a few seconds I got used to it. Did it improve the view? It was marginal, but at times I think that I could see just a little more.

I don't have many filters, but I've never really tried coloured filters on the planets before.  I'm not a big fan of monkeying around with various filters, during a session.  I prefer either to stick to the one or none at all.  Having said that, I do like to try a neutral density moon filter, with and without on the lunar disk.

19 minutes ago, symmetal said:

@neil phillips, @CraigT82, @Saganite, @Kon Thanks for your kind words. 😊

The stacked image of Mars didn't look all that special and i was very surprised when I just applied a saved heavy process in Registax and everything appeared. Here's the stacked tif if anyone would like a try.

2022-10-09-0100_8-U-RGB-ZWO ASI224MC_Gain=300_Exposure=4.0ms_17_lapl5_ap7.tif 2.75 MB · 0 downloads

I was disappointed with how Jupiter turned out. I've just restacked them with different percentages so will have another go.

Scopes out tonight for another try, but not sure if the clouds will cooperate.

Alan

I did a little with the image in RegiStax 6...  I think yours is better and doesn't have a blue border round it.

1 hour ago, cajen2 said:

In your place, I'd try the cheapest option first - a filter for your frac. I recently read (it may well have been on here) a review of the three Baader filters which purport to combat CA. The Contrast Booster won over the Semi-Apo and Fringe Killer. I bought one, even though I have a dob, simply because it's also a good planetary filter. So if you bought the CB and it didn't reduce CA enough, you haven't really lost anything.

I've gone and ordered the Baader Contrast Booster from @FLO, so I'll give that a try (weather permitting).

1 hour ago, cajen2 said:

In your place, I'd try the cheapest option first - a filter for your frac. I recently read (it may well have been on here) a review of the three Baader filters which purport to combat CA. The Contrast Booster won over the Semi-Apo and Fringe Killer. I bought one, even though I have a dob, simply because it's also a good planetary filter. So if you bought the CB and it didn't reduce CA enough, you haven't really lost anything.

I've been using a Wratten #8, as a cheap man's CA filter.

1 hour ago, ollypenrice said:

The Barlow does not affect in any way the number of photons from a planet which arrive at your camera. The light entering the front of your OTA has no idea whether or not there is a Barlow at the back of it so it is the same light. What the Barlow does is distribute it over a larger number of pixels, meaning each one receives proportionally less light in exchange for higher resolution. Since we can collect photons over time this matters very little in planetary imaging since the total exposure time is short anyway. A deep sky imager might feel differently since exposures are measured in hours.

Olly

I was going by the Inverse Square Law, as in you effectively double the focal length of the telescope and the light levels being received drop to a quarter of what the originally were.

If you look at my signature below, you can see that I already have a SW 200P Dobsonian and a SW Evostar 120 achromat.  I also have a friend's 4.5 inch Meade reflector in storage, here in my spare room.

I've been dabbling with imaging with the SW Evostar 120, using a ZWO ASI224MC camera, with mixed results.  I've been recently trying to image the gas giants with some success, but as expected, I'm having to deal with chromatic aberration from the achromatic reflector.  I don't know if one of the Baader range of visual filters would help this situation or not.

I see that some people use their Dobsonians untracked, but I'm not sure if that would work for me (or even how to do it successfully).  I've been using my EQ5 GOTO mount for imaging, the only imaging I've done with the Dobsonian has been with a smartphone up at the eyepiece.

I've been toying with the idea of getting a SW 127 Mak and mounting it on the EQ5, for gas giant imaging.  I've also recently bought a 2x Barlow for increasing the size of the target in the camera frame, but obviously the Barlow cuts down the light entering the camera by a factor of four.

Should I look at buying a SW 127 Mak or are there other options (less expensive), that I've not thought about?🤔  Ideas are welcome...👍

28 minutes ago, bosun21 said:

Have you tried the semi apo filter or the contrast booster filter? This helped a great deal in eliminating the CA

I've been using a Wratten #8 filter for that, as the filter you mentioned are rather expensive and hard to get, at the moment.

You can see some of the CA on these images taken with my SW Evostar 120 achromat.  Coming from a SW 200P Dobsonian, it was quite noticeable.

11 hours ago, gerardsheldon said:

malc_c, thanks so much for your instructions. I was easily able to access the MB. . 

There is a bit of leaf under the MB. See first photo.  That may be the problem. Otherwise the MB looks OK and is one of the old ones. I attach other photos.  I tried to take out the mother board with a little tug on the wires (not enough to cause any physical damage).  i got a bit nervous about static electricity. I was wearing an anti-static wrist band though.

The leaf probably got there via the polarscope hole.

Can you please advise me on how to remove the bit of leaf without causing any static electricity issues. 

Gerard

 

Would a plastic nozzle connected to a vacuum cleaner, not do the job of removing the leaf?

13 hours ago, malc-c said:

Its a choke / inductor.  It basically replaces the large component L42 on the old board

That was my thinking too, but wasn't sure.  I guess the reference clock (or similar) may interfere with other things, causing RFI and other EMC issues.  That would also explain why my EQ5 Pro GOTO kit has a clip on ferrite on the DC power lead, going into the motor controller.

1 hour ago, malc-c said:

How old is the HEQ5?  - If it's still within its warranty period then I would suggest contacting the retailer.  If its a few year old then chances are it will be the older PIC based boards as the new revision that uses ARM processors have only been fitted in the past 18-24 months.  Accessing the board isn't difficult

1. Remove the 6 screws from the plastic plate covering the two stepper motors (the L shaped panel with two circular mounds)
2. This gives access to the screws that secure the curved panel that has the polarscope hole  - Remove the curved panel
3. This gives you access to the connectors on the HEQ5

 

If the board looks like the one shown in the image then the PIC Microcontrollers are on the underneath.  You should be able to see them without removing the board - they are two IC's that are about 1" long, one in the centre the other to the left, at the rear of the board.

For comparison here is an image of the new board on the left and an old board on the right.  If you can see the large copper coil then you have a new ARM based board which requires a certain type of programmer that only serious hobbyist would have.  If you don't see that large copper coil, and can see components on the underside of the board as mentioned then you have an old board that can be repaired. 

Let us know what you find and then we can see what action we can take. 

I'm curious why the newer board has a toroid on it.🤔

1 minute ago, Steve Ward said:

Final stage of processing in GIMP.

"Colorify" in "Colours , select the Yellow box then "Custom" , then knock the Green level down to 230 from 255 ... 😉

Thanks. I wasn't sure if it was it was a special filter for a certainly wavelength of light.

How do you get the lovely yellow colour?

2 hours ago, chiltonstar said:

Good idea - maybe me just overdoing it a bit on a file that isn't sharp enough. This is the stacked, unsharpened file.

Chris

I just re sharpened your original, using RegiStax.

I noticed it down last night, glad it's back up now.

11 hours ago, cajen2 said:

There shouldn't be any CA as your scope's a reflector......😉

That being said, I've seen some CA caused by a cheap, plastic lensed Barlow!😱