William Optics Zenithstar 61 on a SWSA

[daveangie0110]

Hi All

I am thinking of getting the New William Optics Zenithstar ZS61 to be used with my Star Adventurer, if anyone has one of these already on a Star Adventurer with the flattener attached to a DSLR do you know what sort of exposure times i could expect to get with good alignment.

[SteveNickolls]

Hi, I too would be interested in any comments from an early adopter of the WO ZS61 on the SA mount. Looking at the telescopes specification its 1.45kg weight is well within the limit for the mount to hold but at 360mm focal length would be expecting to use a guider for RA. I would however be pleased to hear of experiences showing otherwise :-)

Best regards,
Steve

[geordie85]

I've managed 1 min exposures without trailing from a very quick and rough polar alignment with my WO star 71 and canon 600D so I'd imagine the new, lighter and shorter WO zs61 will work perfectly fine on the star adventurer. In fact I'm thinking about getting one as a grab and go for dark sites.

Probably could have got longer subs if I'd actually took my time to polar align properly but it was a very quick test in my back garden after work. 

[rl]

I imagine many will be looking hard at exactly this combination for all the reasons mentioned above. I've already ordered a ZS61 from FLO for my star adventurer while the price starts with a "3" which I suspect won't last long the way the exchange rate is going. Matching red option of course...

Will advise on the results in due course...... 

[agthomson]

I've got this combo (in red ofc), and the forecast for tomorrow night is good, so hopefully get a 1st light with it.

Sadly, i'm imaging with a Sony camera, so I have to limit my exposures to 30s (non-bulb) to avoid the dreaded star-eater syndrome, so can't advise on exposures really, but could give a couple a go.

[ronin]

2 hours ago, agthomson said:

I've got this combo (in red ofc), and the forecast for tomorrow night is good, so hopefully get a 1st light with it.

Sadly, i'm imaging with a Sony camera, so I have to limit my exposures to 30s (non-bulb) to avoid the dreaded star-eater syndrome, so can't advise on exposures really, but could give a couple a go.

Which Sony have you got?

I have the A350 and could not find Bulb, the S (Exposure duration) goes to 30 sec.

Then one day by accident I fell over Bulb on it under the M setting.

Just check yours it may be the same. Set the top dial to M and then turn the finger wheel all the way - Bulb appears as an option at the end. Do not ask me why it is not under S as in Exposures up to 30 sec then Bulb for "anything".

[agthomson]

On 9/10/2017 at 22:57, ronin said:

Which Sony have you got?

I have the A350 and could not find Bulb, the S (Exposure duration) goes to 30 sec.

Then one day by accident I fell over Bulb on it under the M setting.

Just check yours it may be the same. Set the top dial to M and then turn the finger wheel all the way - Bulb appears as an option at the end. Do not ask me why it is not under S as in Exposures up to 30 sec then Bulb for "anything".

Bulb is there, but from what i've read about Sony cameras is that they do some sort of weird noise reduction algorithm when in bulb mode for some cameras, and for exposures > 4s regardless of bulb or Shutter priority (I think) for others. Essentially this removes some stars as it thinks they are noise.

Link to article (external)

 

 

[rl]

As promised.. a few photos of the new ZS61 on a SA mount before first light (hopefully tonight??):

1) with a 30mm Vixen LV. mag *12, field 5.0 degrees

2) with an 11mm Nagler, mag *33, field 2.6 degrees

3) with a 3.5mm Myriad, mag *103, field 1.05 degrees

4) with a Canon 1100D plus field flattener 6 taken from my GT81. I'll try this one first before splashing out on the proper one. The focal length reduction should help hide poor alignment

The main point is that balancing is easy. All these shots were taken with the RA and DEC clutches loose and the counterweight adjusted for best balance. My old SHDF75 would balance on its own but not with heavy kit on the end.

[AdamT]

Just been looking at this thread and thought I would add my experiences.

I purchased from FLO a few weeks ago along with the flattener after having reservations about its limitations, it wasn't intended to be used on my SA as I had just acquired a AZ-EQ6. So when it arrived i thought id test it out on the SA seemed to balance ok with my D810 attached. Earlier this week it was clear and not forecast while not having the time or energy to get the AZ-EQ6 set up I grabbed the SA & little ZS61 with Andromeda in mind after a quick PA I was ready (took a while to locate M31) but I managed to get 18x60sec subs at ISO3200 (plus darks & flats), the M31 image is on a full frame sensor with just a tiny slither cropped from the edges to get rid of the stacking artefacts.

The FOV is massive with this sensor compared to what i had previously (ED80 & Atik 420mono). I did need to purchase an M48 DLSR adaptor as the usual M42 DLSR adaptor put the spacing out and showed elongated stars towards the corners. The flattener is awesome its got a nice little camera rotator built in and about half way along it unscrews to enable a 2" filter to be screwed in this was a big selling point for me due to a street light in close proximity, another plus point is it all screws together with no compression rings which I like.

 

 

[rl]

Lovely shot...That is really valuable input.

I think you have just persuaded me to buy the correct flattener...

RL

[AdamT]

On 22/09/2017 at 21:55, rl said:

Lovely shot...That is really valuable input.

I think you have just persuaded me to buy the correct flattener...

RL

Thanks, make sure you get the M48 T ring and not adapt a M42 to M48 as the spacing is critical  

[rl]

The deed is done...

Yes, I've made exactly that mistake before..I already have the larger T-ring.

Thanks, RL

[8472]

Has anyone imaged with a 2" filter fitted in the field flattener, at all?

I'm getting some odd shadows/halos around brighter stars, with my 2" SW UHC filter.