A three-season down sleeping bag is a core item for ultralight backpacking because it offers the best combination of warmth, light weight, and seasonal versatility. I prefer a mummy style bag rated at around 30 F for mountain backpacking. The mummy design eliminates drafts, I can wear extra clothes inside and "mummy up" to extend the bag's warmth on cold nights, and I can open it up and use it as a quilt on warm nights.
The popular Mountain Hardwear Phantom 32 sleeping bag (with a temperature rating of 32 F) has been around a few years. Its main features are 15 denier (0.85 oz/yd2) shell fabric with DWR, 800 fill power down, a full length side zipper, and a six chamber sculptured hood.
It has received a few refinements along the way, and Mountain Hardwear deserves kudos for keeping the upgrades nearly weight neutral. The original Phantom 32 had a 2/3-length side zipper and weight of 22.7 ounces, while the current bag has a full side zipper and weighs 23.1 ounces. Weight saving refinements throughout the bag nearly offset the added weight of a longer zipper.
The Phantom's lightweight shell fabric has a very soft hand, and its taffeta lining is very durable. The #5CN YKK zipper auto locks, so it doesn't open when you expand the bag, and it operates from outside or inside the bag.
ARTICLE OUTLINE
- Description
- Performance
- Comparisons
- Assessment
- Specifications: Manufacturer, Year/Model, Style, What's Included, Fill, Construction, Measured Loft, Manufacturer, Stuffed Size, Weight, Sizes, Fabrics, Features, MSRP
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# PHOTOS: 6
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Discussion
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MH has had their Phantom series EN tested (look on their site) and their recommended temp ratings are supported, no matter what brand you prefer. These are excellent bags.
One main difference is I believe the 45 is quilt stitched and does not have raised baffles in between the panels.
Hello
I have both bags. I will do a side by side comparison and post later.
Jim
Interesting that the 45 is 6 ounces lighter than the 32 yet it only rates at 3 degrees cooler. Looks like the 45 is slightly under rated where the 32 and 15 are both over rated.
In a recent duscussion with a manufacturer I found out that not all laboratories, licenced to perform the EN-testing, use the same manikin nor the same temperature sensors, so every result from the EN-test should be regarded with some suspicion.
There is a 5% m2K/W maximum variance using the old EOG guidelines. Using the current EOG guidelines the worst case variance is 3%.
National laboratories, such as NIST, would expect to measure an insulation material at ambient temperatures and obtain agreement to ± 1%, accredited laboratories within ± 3%, and industry test laboratories, such as mine, to within ± 5%. Accredited lab fees start at $500 – $600 per sample. National laboratories cost about 100X per sample. If you want your favorite cottage industry manufacturer to afford an EN13537 test, please consider the above.
Fear, Uncertainty, and Doubt (FUD) is a classic marketing maneuver used by companies in an attempt to have consumers ignore objective scientific data and accept THEIR subjective marketing messages.
Isn't my color prettier?
Doesn't mine LOOK warmer?
My style is more fashionable.
Mine was featured on a TV show.
We (Marketing Dept) rate this as a 0F bag. The EN 13537 standard LLimit rating is only 22F but you know what? Some of the labs use different thermal dummies and temperature sensors which don't yield the same result.
Richard, I had to read your post twice, well said on multiple levels.
Scott,
Thank you.
+5 on Richard's post!
Cheers
I've seen Phantom 32s in two other stores and all were low on loft. I still contend the Phantom 32's temp rating is optimistic, just as the Megalite's rating is conservative.
That said I have a VERY warm, high-lofting Mt'n Hardware minus 20 F. bag of Polarguard Delta that IS warm at that temp, and a bit below. Heavy and bulky but really WARM.
What would you rather have, the bag with the highest loft or the bag that was the warmest. While high loft is likely to be the warmest, other factors dictate it's not always so. What I find lacking in this review is any objective, scientific measure I can use to compare with other bags.
How about for every bag you test, you include a test where you put a bag length tube full of hot water in the bag starting at some consistent temperature, and also some consistent ambient temperature and meausre how long it takes the water temperature to drop 10 degrees? Or find some other objective test methodology that suits you.
I haven't heard of the EN test, but I think some cheaper litmus test such as I've suggested would be useful for comparing bags.
Eric – you have never tried a Phantom but believe the temp ratings are optimistic?
Perhaps I'm reading this the wrong way, so if I do my apologies, but it's not about a manufacturers specific test vs the EN-test but variance between the results of the EN-tests, depending ong the lab that performed the test.
While I know that every tempaterure indication should be met with some suspicion, so also the temperatures given by the EN-test, I at least thought that one advantage of the En-test was that all bags that were being tested could be compared. Now, at least I get the impression that even that isn't the case since the different labs that are licenced to perform the test, can stay inside a legal framework while still differing quite a lof in how they perform the test. And apparantly, the different labs that perform the test have come together to discuss the issue. Although I don't know the outciome of that discussion, it does seem to mean that there is something going on.
Or, in other words, if one lab tested a sleeping bag with a manikin that differed in size and in weight and with almost half as many temperature sensors as another lab, should or should we not exspect a noticible and significant difference in temperatures? An open question and I hope to find the answer here?
I am still trying to get my head around the difference baffling makes to warmth. If two bags have the same loft and same fill, but one is sewn through and the other is baffled, how do we work out likely differences in warmth between them…or is there a difference?
FWIW, the Phantom 45 is baffled, not sewn-through. The Phantom jackets, however, are sewn-through.
Richard has pointed out the (2.8%?) differential in warmth up to a nominal level of insulation. Once you get more significant loft, though, there becomes more of a difference.
When sleeping bag loft is measured, it's basically taken from the highest point… so although a sewn-thru bag might have 4 inches of loft and a baffled bag might have 4 inches of loft, the baffled bag will have a consistent 4 inches of loft. The sewn-thru bag, on the other hand, will only have that 4 inches (2-inch single side, for sake of argument) at the middle of the down chamber. At each stitch line the loft will be zero. If you were to divide a 5-inch spaced compartment in half, then, you'd have 2 inches in the middle ending 2.5 inches later in 0. That might not be as important in a 40 or 50 degree bag (although when my 40* sewn-thru bag gets into the mid-40s I can quite distinctly feel the cold through the stitch lines), but when you get into warmer bags and more loft it can become significant.
A sewn-through bag is basically uninsulated at the stitch line. To determine heat loss you can't just average the thickness. I've done energy calculations for buildings and you quickly reach a point where no amount of wall insulation will make up for uninsulated surface such as single pane windows. An extreme example for visualization would be a sleeping bag where one end is 4" of down and the other end is just a sheet. You need to put insulation on the "sheet" end before adding to the 4" end.
Sewn-through only performs well in warm conditions (probably above freezing) or with synthetic insulation where one batt is sewn to the outer shell and another batt is sewn to the inner shell, and the stitch lines are offset.
Well, yes, that all makes sense to me, but when Richard commented on the relative warmth of the Nunatak Skaha versus a PHD minimus, he seemed to discard the difference in construction and rated the Minimus as being slightly warmer. This 'baffles' me, as I know from personal experience that the Skaha is warmer. I ask here, as some of the other similar rated bags available, such as the Caribou, use sewn through construction. How do we compare these to a bag like the Phantom?
Hi Tom
I am going to stick my neck out here and answer your question without hard supporting evidence. You be the judge.
There are two competing standards for the assessment of sleeping bags: the European EN one and the older American ASTM one. (That doesn't count the off-the-planet guessing done by marketing departments.) The results of much careful EN testing has been the revelation that many American bag ratings are just so much pie-in-the-sky wishful thinking. That does have hard evidence, btw.
What would you expect the reaction would be from some aggrieved American companies? A public admission that they were misleading the public, or a FUD campaign?
The claim that different labs can get different results under the EN standard is correct of course. I say 'of course' because the science and Standards communities know that ANY measurement carries with it some measure of uncertainty. (eg: What's your GPS position?) To claim that the EN standard gives different results depending on which lab you use and *therefore is unreliable* is a classic ploy for FUD merchants.
How many temperature sensors you use on a copper manikin is not critical. What matters is whether the sensors are calibrated. One calibrated sensor is infinitely better than half a dozen uncalibrated ones.
An indication of the reliability of a measurement is that an uncertainty figure is quoted. Which would you prefer out of:
* 20 F with an unstated uncertainty of +/- 20 F
* 25 F with a stated uncertainty of +/- 5 F
Me, I would believe the 25 +/- 5 F figure, but I strongly suspect the 20 +/- 20 F figure would be very strongly biased in just one direction! That is, the real result was somewhere in the 20 – 40 F range. A cynic would believe the 40 F end of the range.
That labs performing EN testing should get together to discuss results is quite normal, and happens right across the spectrum of Standards testing. It is standard practice to have 'round trials' between the labs as well – been there, done that.
I have also seen some vendors quoting the EN Extreme rating for their bags as the normal or typical rating. Apparently Joe Public is not expected to have any brains.
Cheers
Jim,
Did you ever post a side by side comparision of the Phantom 32 and the Phantom 45?
Manfred
Manfred,
The EN Ratings for the 32 and 45 are as follows:
Phantom 45
41 F / 5 C
32 F / 0 C
3 F / -16 C
Phantom 32
37 F / 2 C
28 F / -2 C
0 (or -2) F / -17 (or -18) C
The good news is that despite protestations by several buyers on this forum that the Phantom 32 isn't warm enough, the series in fact beats the EN norm for the advertised temp rating.
The bad news is that a number of Mountain Hardwear sleeping bags CURRENTLY fall short of the EN norm. A good number of their ratings were only roughly on par with EN norms. They'll have to do some beefing up in coming years. For instance, take a look at the Ultralamina 0 on any European retailer site, and you will find the EN Limit rating is tested to be 14 F. The Ultralamina 15 tests at 23 F. The Ultralamina 32 tests at 36 F. (Note that the Ultralamina 45 comes in at 43 F.)
The Mountain Hardwear bags that do beat the EN ratings are the Conness 32 (24), Lamina 35 (32) and 45 (41), Merced 32 (25), Phantom 32 (28)and 45 (32), Piute 20 (12), and Switch 35 (30).
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