Quote:
Originally Posted by Digital_Artist
My calculation my calculation on weight was:
GSO RC 8" (metal) 7.5 kg
DSLR camera 1.0 kg
Orion Mini AG link http://www.optcorp.com/product.aspx?pid=210-16639
package 0.6 kg
Ring, plate 1.5 kg
Total 10.6 kg
Is the calculation correct or should i add something? Even though prescribed payload for HEQ5 pro is 15 kg but it is said that for AP it should be less than 10 kg.
However, in some other places i read that if the balance is right then payload can be increased. Even in an youtube channel one person said that he put up 50 pounds of weight on EQ6 pro even though its maximum capacity is 40 pounds and it works. If it works for EQ6 pro why not HEQ5 pro? please explain. |
Yes, generally you want the total weight to be well less than the prescribed payload for imaging purposes. There is a rough % of total but I can't remember it off the top of my head. Maybe 75% of max payload? I'm sure someone will know.
I wouldn't get to excited about one person saying they have gone well beyond the maximum payload of their mount. For every one person who has success, there are likely to be many more unsuccessful attempts. Just as example of someone who had issues imaging with a RC8 on a HEQ5 mount, dugnsuz (Doug) ended up selling his RC8 because his setup was too heavy (see threads
here and
here). You also have to consider Doug was using a reducer and still having problems. Guiding issues will be even worse if guiding at the native focal length.
Also, I'm not sure how well the Orion Mini AG will work with the setup, particularly at the RC's native focal length (then again, I have had success using my Skywatcher finderscope as a guidescope but I still need to do more testing). You might need something with a longer focal length to get better guiding. If you do, then that will add more weight to your payload. I use an old 60mm f/11 tasco refractor as my guide scope (see picture
here). I generally only go out to 5mins and get round stars most of the time. However, I just did two 1hr sessions of going out to ten minute subs over the last two nights and probably 80% produced pretty good stars. I also don't use a focal reducer.
This is what I was able to achieve with my RC8 and a modded Canon 30D. I have just finished collecting 9hrs of The Running Man Nebula which I will process over the coming week.
BUT in saying all this, I agree with what a lot of people are saying. Imaging is a tough ball game and you need to work your way up. Wide field imaging is more forgiving. A lot needs to go right if imaging with scopes of long focal lengths such as the RC8. I spent several frustrating months sorting out guiding issues when I started imaging with my 8" Newt. The RC8 (with no reducer) is less forgiving so I've had to tighten up my guiding again.
I hope all this helps
Dan