Montbell Ex Light Anorak- A Contrarian View

"It seems like a lot of thier older bags picked up a bit of slack about being underfilled. IMHO, I think this is somewhat due to the fact that the bag's stretch "

Gosh no. You could hold the sleeping bag up to light and there was virtually NO down in some of the baffles. There are a lot of reports of this even with the newer bags.

:) I did say somewhat… I know that in some cases, folks also reported what you describe.

Edit to add: I know it isn't always an option, but this does make it nice to be able to actually put hands on an item before buying it. This way at least the item can be checked out before bringing it home.

You should be using a quilt anyway.

Come on, Son!

Quote: ""Taking this one step further, the amount of down in a jacket is more directly related to the jacket’s warmth than the loft of the jacket. Jackets do not have to be designed so the down is allowed to fully loft; it can be packed more densely or partially compressed in the jacket’s shell, and the jacket will be just as warm (though it is true that many manufacturers do allow the down to more fully expand so the jacket looks puffier, because puffier jackets are perceived by buyers to be warmer jackets)."

Taken from Richard's earlier study"

The natural extension of this is that the down compressed under you when sleeping in a bag provides just as much insulation as the down above you. Which obviously isn't true.

So at what point does more loft start to not be needed? If this is true, I'm surprised the amount of down compression (as designed into the garment/bag) isn't some fully tested, extensively debated value on this forum. Or maybe it is and I've missed it.

Am I carrying around excess fabric in my down items?

Steve

I own the Anorak and have been nothing but happy with it. I actually tend to believe it's a bit warmer than my UL parka. I also haven't had any issues with the down shifting but I'm now keeping my fingers crossed it won't become an issue in the future.

Only wish I understood all the data in the beginning of the thread! Pretty much just a bunch of pretty colors to me.

Steve,

Up to ~2-2.5x density (half the loft but the same amount of down) in jacket baffles is fine. Laying on it will take you way beyond the linearity point; quilts are smart (smile).

Note that PET (Primaloft One aka Gold, etc.) is typically manufactured not for the maximum loft but the knee point where the insulation value is maximized by increasing its density.

"You should be using a quilt anyway.

Come on, Son!"

I have a few of those too… :)

Richard,
Thanks for the graph. But I don't think the graph shows that there is a sweet spot for compressing down (or a sweet range); the graph shows that thermal conductivity reaches a minimum the denser the down is.

I'm assuming the graph is for a set amount of down, for a set surface area.

The graph would need to show the curve coming back up in thermal conductivity as the density goes beyond a certain point. Otherwise, the graph supports the idea that the best insulation is on the bottom of my bag.

Steve

Steve,

This chart shows a higher density range so that you can see the down's performance knee (major slope change) begin:

Steve,

The graph shows thermal conductivity, which is in units of W/(m*K). Note that it's per meter so as you compress the down, the thickness changes in direct proportion to the thermal conductivity. So what's important is the slope not the absolute value. Richard's graph shows that the slope doesn't change for a factor of about 2x increase in density (and thus 2x decrease in thickness.) The knee point is where compressing the down further results in a decrease in total insulative value (thermal conductivity times thickness).

Andrew

All of this sounds like a perfect inspiration for a Gary Larson Far Side Cartoon…
a gander of geese studying homosapiens to some hair-splitting extreme…
for those of us old enuf…dontcha miss it?!

So all the advice on loft of a sleeping bag above you corresponding to a certain degree of warmth isn't exactly the real deal. Instead, warmth should corresponded to the amount of down above you.

Steve

Steve,

Yes it is the closest correlation factor to warmth, outside actually measuring the heat conduction in a laboratory.

After seeing a Ghoat Whisperer a few days ago I can see that the Ex light has more loft.

What's that, Stephen? A goat whisperer? :)

Yes William, it's a character on TV who whispers at goats ;-)

You called…?

Richard, Kenneth and others – I very much appreciate the test you are doing to these jackets. I did my own simple real-life test

I have the Exlight and the Ghost Whisperer and took them both out on two overnights in New Hampshire's White Mountains Presidential Range. Temps were 15 to -5F. I had a Capilene 4 baselayer and a PossumDown midlayer on with the jacket. Tried each jacket for 3 hours each, both in the morning and in the evening.

Results:

No comparison.

Ghost Whisperer is WAY warmer. Simple as that. My body tells me so when I shiver in ExLight.

But, that said.

Neither, however is warm enough for these temps. I would use Nunatak's Skaha or Goosefeet for when it gets into 10s and below. Much better down to weight ratio and much warmer. You'll look like a blown up potato, but who cares.

Dang you people that are making me contemplate buying a new piece of gear. I bought a UL Down Inner in 2008 (brand new for $80) and it was one of my best purchases ever in backpacking gear. It has literally been out for hundreds of nights and weighs a scant 7oz.

This anorak weighs about the same and even adds a hood so it has me tempted.

My question is how is the fit compared to my 2008? I am trying to decide between a M and L and heard that mont bell's run larger now than they did then?

A few other questions, this seems to be out of stock just about everywhere, is that because demand is more than supply, because they are doing a minor redesign, or are they just caught up in the port mess?

I also noticed that unlike my 2008 version, the boxes are not completely enclosed and it looks like down can migrate from box to box. I wonder if that will cause a problem. I want it to be as warm as my old UL Down Inner.

Bradford,

I have an old UL Inner parka and love it, just like you.

The newer ones do NOT have as much loft, period. I've looked at several, new and used.

The Ex Light is about like the current UL's for warmth, IMO, but not as warm as the old UL's. Not sure how to quantify it but I'd say at least 5deg difference, maybe 10.

I have used my Anorak on one trip and like it a lot – I just accept that on colder trips I'll take my good 'ol trusty UL Parka ( weighs 8.9oz, by the way – and that's w/the drawcord waist that I added myself!!!).

Thanks Todd. Perhaps I will just save my money. I really don't need a new down jacket, and just wash my old UL Down Inner Jacket. I also have an old Mon-Bell snap vest that I really like.

Hi – strongly considering one of these for use on the PCT. My concern is that I'm kind of hood-challenged… I have a very large head, and find standard sized hoods often don't work for me. For instance on my Patagonia UL down hoody and houdini the hoods fit too snug for me to fully zip up the jacket… Arcteryx, however, seems to mostly work for me (especially 'helmet compatible' ones :P). Can anyone with a big head / long neck who owns the anorak please comment on how the hood is sized?

Lachlan, I wear size XL hats but, don't have a long neck. The Anorak hood is VERY big on me and tunnels forward from my head significantly more than any other MB jacket of the same size.

I have two Eddie Bauer down garments, both First Ascent brand. The first was purchased back when EB parted (thankfully) from Speigel and brought our First Ascent. It is the down jacket I'm wearing in my avatar and it has decent loft. My second is a down vest with the new DWR treated down. Unfortunately EB elected to UNDERfill that vest a bit. Ex. That collar is wimpy and wont' stand up like the jacket. I'm not happy but it was a gift and I sorta can't return it. (Plus I've already returned a First Ascent Karakoram 0 F. down bag for a terribly ill-designed draft collar.) In any case EB needs to be SURE First Ascent garments are first rate in every respect. Hint EB, look at Feathered Friends and Western Mountaineering for how to do it. So is EB trying to save on fill due to the expense of the DWR treatment? I'll be using the vest in mid Oct. in a northern Nevada mountain hunting trip at altitudes up to 10,000 ft. so we'll see how it fares, especially under my hard shell parka. QUESTION- Would narrow taping the seams of sewn-through down garments reduce the heat loss at those seams by much? Maybe worth a try. Of course it would add some weight, maybe 2 ounces to a vest. In any case EB needs to be SURE that First Ascent garments are first rate in every respect. Backpackers ain't poseurs in a mall. Hint EB: Look at Feathered Friends and Western Mountaineering to see "how it's done".

I think you will be fine. Here is a pic of me (my head circumference is 23.5 inches) wearing an Ex light down anorak (medium) with a Black Diamond half dome helmet. I can zip it up completely and still move without issue.