EQ3-2 Subs

[Purplehayze104]

Hi All, just out of curiousity was wondering if anyone uses an eq3-2 pro or upgraded eq3-2, what sort of sub lengths would I be able to get with synscan? I know its not the best size mount to try A.P but budget an girlfriend have set limits to what I can afford. am using it with a 6" skywatcher newt. so any advice would be appreciated, thanks

[JamesF]

The 150P is fairly hefty to put on the EQ3-2 for imaging, but if you set it up really carefully you may well be able to get exposures into the minutes.

Your biggest problem is likely to be getting the camera to focus. You may need to look at moving the mirror up the tube with some longer bolts to make that possible.

James

[RikM]

They fixed the focus problem with the change to the 1.25"/2" Crayford and black diamond colour scheme. The old blue ones had that problem but the newer ones are okay.

I have used a 150P on a standard box-ali tripod EQ3-2 and after transferring the head to the steel pipe tripod from an EQ5/HEQ5/AZ4. I found no difference in the max sub lengths by changing the tripod. A good polar alignment was key for me. I could get 60-90 seconds regularly and could keep about 2/3 subs. The other 1/3 showed jittery stars usually because of the wind. If imaging higher up near the pole, then 2 min was possible with the same keep rate.

[JamesF]

They fixed the focus problem with the change to the 1.25"/2" Crayford and black diamond colour scheme. The old blue ones had that problem but the newer ones are okay.

Ah. Fair enough. I thought the inability to bring a camera to focus was one of the reasons they brought out all the PDS models.

James

[RikM]

Ah. Fair enough. I thought the inability to bring a camera to focus was one of the reasons they brought out all the PDS models.

James

I don't know about other camera models but certainly Canon EOS DSLR's with a Baader MPCC, a low profile 2" T nosepiece or a standard T-ring screwed onto the 1.25" eyepiece adaptor focus fine on the standard single speed Explorer 150P and 250PX. I can also use an SXV-H9 with slimline filterwheel with no bother. Perhaps some other cameras need more back focus?

With PDS models I think the draw-tube doesn't intrude into the lightpath quite as much as the single-speeds and certainly the dual-speed gives you more focus control.

[JamesF]

Ahhh, I wonder if the MPCC helps in that situation? It increases the effective focal length slightly, doesn't it?

James

[Purplehayze104]

thanks for your replys, luckily i have the black one an have tried the dslr camera upto the scope and i can focus it, unfortunately

not had the best of skys to actually try imaging anything coz of hazy cloud that always seemed to roll in as it got dark tut,

hope to give it a try soon as eager to practice.

[astrosathya]

Hi mate,

Even a single star visible is good for practice. I tried my first attempt at guiding when, owing to clouds, Sirius was the only star visible to my scope. I did well that night, which also made me more confident. If you do a Periodic error Correction for your EQ3-PRO, and also use a finder guider, you could get about 90 second subs, but most of them will be useful. I have only read about finder guiders, but by the looks of it, they are easy to use.

[RikM]

Ahhh, I wonder if the MPCC helps in that situation? It increases the effective focal length slightly, doesn't it?

James

Doesn't seem to. The SkyWatcher one acts as a reducer, and the Paracor as an extender but the MPCC seems to leave the focal length unchanged. I didn't notice any significant difference in field of view when I switched from a plain 2" nosepiece to the MPCC.

[RikM]

Hi mate,

Even a single star visible is good for practice. I tried my first attempt at guiding when, owing to clouds, Sirius was the only star visible to my scope. I did well that night, which also made me more confident. If you do a Periodic error Correction for your EQ3-PRO, and also use a finder guider, you could get about 90 second subs, but most of them will be useful. I have only read about finder guiders, but by the looks of it, they are easy to use.

If you have the EQ3 pro and get an autoguider working, you should be good for 3-5 min subs at least.

[JamesF]

Indeed not, it seems. The MPCC explicitly doesn't increase the focal length unlike some other coma correctors, apparently.

James

[Purplehayze104]

If you have the EQ3 pro and get an autoguider working, you should be good for 3-5 min subs at least.

all sounds good to me thanks for your comments, im working my way upto a guided system but thought id get to know the mount an start from there with a few goes at A.P hopefully weekend wont be to bad an will try my luck

[lensman57]

Hi All, just out of curiousity was wondering if anyone uses an eq3-2 pro or upgraded eq3-2, what sort of sub lengths would I be able to get with synscan? I know its not the best size mount to try A.P but budget an girlfriend have set limits to what I can afford. am using it with a 6" skywatcher newt. so any advice would be appreciated, thanks

Hi,

I don't have the EQ3 but the EQ5, I think that they are basically the same, with good polar alignment, not polar scope but either drift or the skywatcher routine, I can get about 90s without too much trouble for about 750mm focal length. With guiding up untill last week I could go up to 1200s, but I found out that the ALT bolts had bent last week and since replacement I have not had good guiding. The polar alignment and a perfect balance are the key and make sure that you don't have anything loose or wires flapping around as it will effect your subs, believe it or not even though my mount is on grass and well damped I have noticed that even walking around the mount will cause the PHD guide graph to show a spike and then it calms down, something that can not be avoided with lightweight mounts. Good Luck.

A.G