I finally decided to take the plunge and go for the biggest APM bino, the 150mm 45 degree ED model.
My original plan was to buy the SD version of the 150, but I did not want to take the chance of waiting for that model to be manufactured so I went ahead with the ED version.
Personally, I like the 45 degree angle as it works much better in my observatory when varying the altitude compared to my 90 degree binoscope. Many objects from this latitude do not exceed 70 degrees which I find is very comfortable to view with the 45.
My first reaction to seeing the 150 in person was that it's smaller than I expected.
It's fairly hefty, but not difficult to mount on my Panther TTS 160 mount using the attached D plate.
The included D plate is aluminum, and has a stainless steel edge attached to minimize wear.
Included with the 150 is a very rugged airline type travel case with wheels and a set of 30mm UFF eyepieces providing 27.5x.
I also bought the APM giant fork mount in case I bring the 150 to a dark sky sight and don't want to take the TTS160 out of my observatory.
The APM150 feels comparable to mounting a 6" refractor or 10-12" SCT. It's somewhat short length makes it easy to maneuver, though it's at least 10lbs heavier than a 150mm telescope. Weight is around 40 lbs without eyepieces.
The top mounted carry handle is long enough to find a perfect balance while holding on with two hands. There are multiple tapped holes in the handle allowing a red dot to be attached.
The TTS160 required 24 lbs of counterweights to balance it, and the 150 felt remarkably like my APM 120 when moving through altitude and azimuth. I have manual azimuth ability on my TTS through the use of an adapter I made.
The optics look perfectly clean with no dust particles visible inside or out. The body also is cosmetically and mechanically excellent with no defects that I can find.
I like the slip on style objective caps that come with it better than the screw on type of the smaller versions. They can be installed regardless of the dew shield being extended. The screw on type can be a problem when it's cold outside making it difficult to thread on and possibly touch the objective if your not careful.
It would be a good idea to have either tape or felt to prevent wearing of the paint as the caps are likely going to be on and off a lot if you are fussy about your objectives staying clean.
The dew shields slide out like other APM binos but are stiffer to move, which is probably a good thing so they don't drop back when near the zenith. The best method to get them going in either direction is a wiggling motion, then you can slide it the rest of the way.
The focusers have inserts that allow switching from 1.25" to 2" eyepieces. To use 1.25" e.p's you must place the eyepiece into the insert first, tighten it, then install the insert into the 2" holder and finally tighten the two inch locking collet.
Simple and effective, but more time consuming than the standard 1.25" holders on all other APM binoculars. It would likely annoy someone who likes changing eyepieces constantly.
The focusers move more easily than my other APM binos, making small adjustments in cold weather better. They now feel just right in regards to the force needed. The fit in the barrels is excellent, making the eyepiece very secure with no wobbling when you touch it.
To maintain good collimation when changing eyepieces, it works best to apply light pressure down on the 2" adapter top ring while tightening the collet. It would be nice to have a second set of adapters so eyepiece change outs are quick.
First views were at some distant trees using the 30mm Ultra Flat Field.
Looking at some acorns at the top of an oak tree about 300 yds away with the Sun nearly behind I could see no sign of any color fringing on the edge of the branches and the image was very sharp. Close focus is about 100 feet.
The conditions were poor on my first night out with the APM150 and I only managed a couple views of M42 before clouds rolled in. One thing stood out right away that impressed me was how bright the nebula appeared, with the four stars of the Trapezium very distinct at low power.
Over the course of the last two weeks the seeing has still been poor, but I had one night with excellent transparency that allowed some nice views. Collimation remained excellent up to the highest power used which was 103x using the 8mm Delos.
M42 looks fantastic at this magnification with the Trapezium showing the E star as a distinct dot. Seeing was still causing some slight spiking on the four main stars to prevent F from being seen.
The view was similar to what is seen in my Meade 12" F/8 SCT.
Another impressive sight is the brightness and resolution of the globular cluster M13. Again, it's very comparable to what I see in the 12" SCT using the same powers. This is where the 150 really pulls away from the APM120. It can easily handle much higher powers while maintaining a bright image.
The large exit pupil the 150 provides at any given power really changes the appearance of many objects.
Very faint stars become resolved in small distant clusters like NGC1907 near M38 and NGC2158 next to M35. Open clusters like M37 and the Double Cluster also show more stars that are out of reach in smaller apertures.
Recently I bought the new APM 12.5 HI-FW eyepieces and they are impressive. Excellent eye relief and comfort. Heavy like the Doctor's, but at less than half the price they are a bargain.
Comparing the APM 12.5 to the 12.5 Doctor's, the APM version does have perfect looking stars out to the edge in the 120 and the 150. The Doctor's have what looks like slight barrel distortion near the edge.
They appear equal in the ability to pull out fine detail, but with the marginal conditions currently present I will have to do more testing at a later date.
Looking at the Moon with the 12.5's at 66x in the 150 is simply incredible. The level of detail with that kind of resolution cannot be adequately described. I could not see any false color looking on axis, while just a trace of lime green is apparent if I move slightly off axis.
It's difficult to tell until the seeing gets better, but I would put star sharpness equal to the APM100 and just a bit behind the APM120, which is to be expected.
So far the 120 has shown the sharpest star images of all the APM binos I've tried. The 70 is excellent as well, but I rarely go above 40x to keep the image bright.
On a simple scale of star sharpness, the 100 and 150 are very good, the 120 is excellent and my Takahashi FS102 binoscope is superb.
When looking at stars in open clusters, this slight difference in sharpness is not an issue and can only be seen on brighter stars or if you were looking for planet detail. Not something that I do with binoculars.
It's also very noticeable how the 150 is affected by seeing conditions compared to the 70 and 100mm binos. The 120 does a bit better than the 150 as seeing degrades as well.
I had a chance to compare a friend's Fujinon 150MT to the APM150 and it basically comes down to several reasons why there is no comparison.
The primary reason is being fixed at 25x with somewhat narrow feeling eyepieces makes the Fujinon severely handicapped.
The APM with the 30mm UFF simply blows it away in every category, particularly in sharpness across the field and color fringing.
The large 6mm exit pupil of the Fuji does not work great unless you have darker skies, and best powers for framing many deep sky objects is from 35x to 60x.
The Fujinon has straight through viewing which makes it awkward above 45 degrees for me using the factory pedestal.
The false color in the Fujinon shows up distinctly on bright stars, while making fainter stars less than perfect.
Using a pair of 32mm Masuyama eyepieces to match powers at 25x, I was looking at the Orion Nebula complex during sunset and it was easier to pick out stars in the APM well before they were visible in the Fujinon.
These factors would not be as problematic if I didn't compare the Fujinon against the APM, but the APM150 just takes it to another level.
Overall the 150 is a nice package that provides a lot of punch with a two eyed view at low powers, and is a perfect match to the TTS160 mount.
It is more difficult to mount compared to the 120, especially if you plan on traveling or taking it down every night.
The 120 is satisfying enough to be a keeper. That's why I don't plan on selling my 120 as it combines the largest aperture with the best portability.
My observatory made the choice to go for the 150 very easy, as it delivers exactly what I was looking for by pulling in the objects that always seemed to be at the threshhold of observation in my suburban skies.
I'll still buy the SD version of the 150 if my friend is interested in the ED, but we'll have to wait and find out if the higher end glass version is going to manufactured. My guess would be that the 150ED sales will make the final decision.
I'm sure there is some interest in how the 150 works on the giant fork mount so I will write a seperate review of it shortly depending on the weather.
Attached photos show the size difference between the APM 120, 150 and also the Fujinon 150MT.